#serious-discussion
1 messages · Page 357 of 1
Like obviously you could define a function and just say it's output is the roots of the polynomial
u gotta be juan ponce de leon
But what is a well defined way that isn't approximation?
million dollar question right there
Sadly not
with things like the lambert W function and the erf its been studied and it can be graphed in the complex plane
non elemntary i think
yeah
I found that out and shit felt like I was standing on the edge of it hah
Which is larger
e^pi or pi^e
i found something interesting
by intuition only
Sure
https://en.wikipedia.org/wiki/Bring_radical
@worldly horizon @magic python

We really just defining whatever now, huh
there are many, here is one:
just sent the wiki link for the bring radical mentioned at the bottom
for those who are curious
Wow uhhh so a multivalued series?
no, that is just one of the solutions
if u have one of the solutions could it not be reduced to a quartic with the one root factored out?
either long division or plain factoring
Yes ig
how it feels seeing Riemann get glazed just for plugging complex numbers into the oiler zeta function.
fine then just go to the link to see the gif or whatever
Its not as simple as just plugging it into Euler's series formula, because that doesn't always work, Riemann did the analytic continuation to do this
let me slander fraudmann
goatler solos
go on. post the embedded gif then.
why lol
It’s a Rickroll
I'm thinking of learning Lean before my Discrete class next term. have any of yall learned it?
and how helpful is it
what kind of benefit are you hoping for
i dont see how knowing lean would be particularly useful
proofs
discrete is an inherently proof-heavy/logical class
was wondering if lean would help w this
not really
i mean you could use it, but its not going to directly help you in any way
for an intro discrete math class
if you want to learn it independent of that then yeah do it
I was thinking if I have exposure or practice of learning how to write theorems and proofs in lean, that skillset could benefit me in discrete
i realize now that this isnt a property of just discrete tho lol
ig i could learn it just to have it
kind of, but the way of writing proofs in a proof assistant is different
humans don't write proofs like you do in lean
its almost always significant extra work
go work bih
Unc McDonald's is calling...
NAW
It’s dead
hello!


yep same
lol
hello hanako!





Best way to unbias yourself is by randomly generating opinions.
Depends on the distribution
for example this is stupid imo
lol
nope
not allowed here
no? youre just not allowed advertise.
nobody is allowed to
recruitment is also not allowed
Huh, whats happening here
"Looking for people who—" Yeah advertising.
The or is wild 💀
GA cult days are numbered
The set of statements I have left to make about GA is in bijection with a proper subset of itself
Hi chat
everyone slept
its raining outside
AND LIGHT WENT OUT TOI
ANYTHING WORSE CAN HAPPEN NOW 😭
hi theree
i really want some tips on how to make practicing math a habit every day even when i dont have it in school i still want to become really good at aptitude and solving stuff fast and accurately so some tips would be nice (im in middle school btw)
I guess you have to practice a lot in order to become good at solving stuff
Random question - has anyone been able to sign into mathprograms in the last hour
I've been unable to sign in and I'm not receiving login tokens to anywhere in my email inbox
Know urself
What
yeah ik but like how do I make it a routine every day yk
Practice every day. I'm not sure what else to say tbh
maybe find a way to make math fun? I'm not sure how with with middle school math but once you do you'll naturally get better at it and you won't need a strict routine for it (since it's something you do/think for fun). Maybe try to understand it better, find some applications or talk to people about it. All those might be fun
I have an Instagram profile called nicemath_ where I make math videos using Manim. Anyone who can help me out there, I’d really appreciate it
guys lets be real: 1+1=3
@frozen patio Please elaborate that.
ok
2 = 0
Dumb question
$$ \left(1 + \gamma M_1^2 \right) \sqrt{M_2^4 + \frac{2 M_2^2}{\gamma - 1}} = \left(1 + \gamma M_2^2 \right) \sqrt{M_1^4 + \frac{2 M_1^2}{\gamma - 1}} $$
Is there any good way to solve for $M_2$ without doing the huge expansion?
M_1 = M_2 works 
supersonic
You aren't wrong
I figured it out
Solve[(1 + g M1^2) Sqrt[
M2^4 + 2 M2^2/(g - 1)] == (1 + g M2^2) Sqrt[
M1^4 + 2 M1^2/(g - 1)], M2]
Mathematica for the win
Is calc ab low for a senior in hs?

For people interested in math, then I generally hear calc ab or bc done in senior year, or maybe calc 3 if your school offers it
Some specific schools have programs where you can take a lot more mid to late stage college stuff while in high school, but those are the exception. Alternatively, you can take a summer course or 2 at a college while still in hs if you meet the requirements. But in general for most people I hear them doing calc in college
no, not at all if you look at the entire HS population
or even just the 4 year college bound
there are just a bunch of accelerated progress types in mathcord
No.of soln of sinx+cosx=1 in interval [0,2pie]
Ans will be 2 or 3?..
Help me out
square it
$\sin(x)\cos(x) = 0$
råys
No
I m just confused that either should I take 9pie/4 or not..like after solving the equation it will come to sin(x+pie/4) = 1/root2
And if we equate sinx= 1/root2 in interval 0 to 2pie..then the no of soln will be pie/4,3pie/4 and 9pie/4
But some said u shouldn't take 9pie/4..
Means it will lie on the same line as pie/4
If we look at the quadrant
bangali?
Nah..indian (hindu)
ah i see
squared it, then removed extraneous solutions
the candidate solutions are $\frac{k\pi}{2}$ but some of them are due to -1 getting squared to 1
råys
so you just plug them into the original equation to see if they work
np
Guys can someone join my Microsoft teams school meeting please, it’s in Bulgarian though.
bro left
Random question, but is anyone good at height comparisons here?
tall ask
@foggy meadow did you find the x^x thing or nah?
Me and my teacher were actually trying to integrate x^x the other day, we couldn't figure it out, but it was cool to see what problems came up along the way
I thought $sin^2(x)+cos^2(x) = 1$
yes
Jake
$(\sin(x) + \cos(x))^2 = 1 + 2\sin(x)\cos(x)=1$ in this case
råys
From $(a+b)^2=a^2+2ab+b^2$
Jake
indeed
I love that formula and that saved my time
Give us the cubic one
Which one sum of cubes or difference of cubes
Both
Na.
Natrium
Guys I have a question. How can someone study Einstein's special theory of relativity without even knowing real analysis or even basic calculus
One guy I know claims that

I sob with you
Bro what happened @snow ice
nothing
Sorry, to intrude but does anyone have book recommendation or resources for self studying physics?



do u know alzebra and calculas?
no idk alzebra
Marisa
yo
It is also from the pythagorean theorem
hii
Cloudflare saying they have detected unusual traffic from my network when accessing an article though it's just me alone at home and it's the first time I open a researchgate article today looooool

how long does it take to learn the DI method?
Learning what it is is simple iirc, but learning when to use it may take longer
yea i was referring to the latter
im in hs so i gotta use it for IBP that includes cyclical integration
You might be able to learn it in a month or so (Probably an exaggeration, it's been a while since I've messed with it)
someone is definitely stealing your wifi and using it to do research
Probably could in a week tbh
It all depends on how much exercises you do
Practice is really good if you want to be able to spot when you use it
You could probably learn the basics in a day or two tho
its applicable everywhere where IBP can be done right
DI is IBP
It's just formatted easier to understand
iirc
Idk you could probably do it in a week, maybe even less
Considering you seem to know calc decently enough already
iirc you can find lots of videos explaining it on YouTube, most of the time would probably be getting used to noticing when to use it, that comes from practice
Guys reply
I think Brian Greene is absolutely amazing at explaining relativity: https://www.youtube.com/watch?v=XFV2feKDK9E
But if you don't have a good grasp of the math it'll be hard to derive the Lorentz equations and understand it precisely
a*b=c, can you subtract b from both sides?
Ok fine I'll let them if they do research
What?
what's the original question?
There isn't one. This is a conceptual question, in general.
sure you can. whether or not it helps you is a different thing though.
I tried subtracting cos(55) here but it gave me an incorrect result.
Why?
open a help channel.
no ty
You don’t need to subtract, just multiply ED with cos(55) to get ≈0.573ED and then to find ED you just divide the value of 0.573 by 4 to get an estimated answer of 6.98. Hope this helps
Can someone help me with 24=4 x p ??
Sry I may be a little late
!help
To ask for mathematics help on this server, please open your own help channel or help thread. See #❓how-to-get-help for instructions.
if the whole thing about HCP is that any complex conjugated amplitude based on direction is changed but only reflected as a mirror image then why do they remain pointing the same direction but are still not topologically equivalent? if they are mirroed then surely they are?
cant they be deformed to match regardless if there is a different start
Drink vending machines intentionally drop it forcefully so that your drink explodes and you have to get a new one
No bro I'm not asking how can I do that, I'm asking how's that even possible for anyone? One of my friends claims that.
To strictly answer your question, you don't need to know real analysis or even basic calculus to derive much of "special relativity"
However, you need to know some algebra for sure (for example to calculate the lorentz transformation), and some geometry for example the Pythagorean theorem for light clock calculations
Hey guys, I want to get into college to become an apprentice. Thing is I struggle a lot with math and have a learning disability. A lot of these apprenticeship trades require lots of math or little math. Could anyone give me some advice?
take your time with the concepts and practice a lot
this might seem as generic advice but it's what works for a lot of people
idk much about any learning disabilities though so sorry about that, but what's tried and tested is worth a shot
Okay, would you think getting a tutor would help? I mean they'd have to be patient with me and I learn differently I mean everyone does, and I don't know much about my learning disability I'm diagnosed with it and I know one of the stronger things I struggle with is math so it kinda brings down my hopes for making the decision to go to college, I didn't do bad in school I averaged 70s, my dad says he would pay for it but I'd have to be really committed so there's a lot of pressure.
hi
Getting a tutor does help, yeah
I've never had the need to get one but I know people who did and it helped them improve their grades
Still, I'd first try and teach myself, there are various sources
the best ones being khan academy, and then of course textbooks
if that doesn't work out feel free to get a tutor
Okay thank you
twenty-four minus four equals twenty, therefore, P=20
@gentle birch what's the best way/method to learn division? I can't do division whatsoever
go through worked examples slowly and then practice a lot
could also watch a youtube video
True
start from basics like
40/10
20/2
then go to stuff like 528/13
remember that division is just repeated subtraction
I don't understand
40/10 = 4
how many times can you subtract 10 from 40 until you can't anymore
so you have
40 - 10 = 30, that's 1
then 30 - 10 = 20, that's 2
20 - 10 = 10, that's 3
10 - 10 = 0, that's 4
can you do 0 - 10? nope
so we have 40/10 = 4 with remainder 0
remainder's just the number left at the end, 0 in this case
So for example
20÷2 can be divided 10 times with the remainder as 0
But 20÷2 what would it equal
Okay so basically
can be subtracted* not divided
Ohhh okok
So any division problem you subtract it till you can't and the number of times it can be subtracted till 0 is the answer?
Like the answer is whatever
that's a slow way to do it, there are better ways to do it
but that's one way to do it
that's basically the idea of what division actually is
What are the other ways I've got my notebook open right now
But I need it to be easy
you can look up long division on youtube right now
Okay thank you
not quite, but it answers a question related to repeated subtraction
if you think about it, modulus is repeated subtraction
5 % 3 = 2
15 % 2 = 1
repeatedly subtract until doing so again would yield a negative number
division tells you how many times you could repeat that subtraction, but is itself not the repeated subtraction
interestingly, you could also look at mod as the canonical projection of the quotient by the ideal generated by the second argument
so div is divide the number, mod is divide the space
I think that's cool
then the earth combusts and we all die unfortunately
thank you
👍
you subtract the second argument a negative amount of times
6 7
does anyone know of a method to solving a bernoulli question faster?
just master your current method
Anyone here a expert at pre calc? Need some help
can you please not spam the same message in three channels
dude just write the help channel post
check #precalculus probably. you get faster help from asking any questions you have directly
<@&268886789983436800> spamming too
how did they even spam that i already timed them out
They sent it again so idk
oh wait this is discussion 2
I just say it's spam if it's copy pasted to more than one channel
nvm
no it was definitely spam you were right to ping
Kk
i just thought they sent it after i timed them out
Ah kk
me trying to look for engineering stuff:
google:
maybe this belonged in chill sorry lol
I am definitely buckling under pressure
Funny how I chose this major by my own volition and I am struggling with it
Definitely has to do with time management
math major?
Yes
My friend describes this as "picking an academically challenging degree and then going 'wow this is academically challenging'" haha
Its hard for many of us, dont worry too much about it, you'll get through
patty cake patty cake with no hands
I hope I do
My first year was a disaster, thanks to numerous health issues
I hope this channel is kinder to mee
Sup
sky
can any one say some importent properties of hyperbola
Simple
Existential dread and anxiety about the future
you either need to feel the pressure of an upcoming exam
or have someone threaten you
spite
can anyone help me with creating linear equations
sup
- motivation: be anxious
- creating arbitrary linear equations is incredibly easy, you've probably been doing it forever (y = mx + b bruh)
how's diff eq. vs multivariable calculus? i've heard different things, like it's easier but more tedious. i know it varies greatly br institution, but im curious about others' experiences
Multivariable calculus is similarly tedious
definitely as tedious as Differential Equations
Hi fiscussy 2
^ i agree they are equal
taking intro to proof-writing before diff eq was a mistake
i can no longer compute anything lol
I know it's quite a while later, but I ended up getting a travel whiteboard that I take with me to lecture each day. It's very useful for communicating concepts to friends, and I can draw pictures that are on the board so I can later replicate them to put in my notes. I'm still a little sad that I can't quite work on the same surface as my peers, but this is good enough most of the time
0+0=1
Huh
welcome to the server! a fellow countryman?



on an elliptically fibered K3 surface, there are families of Ricci-flat Calabi--Yau metrics whose Gromov--Hausdorff limit is the base S^2 with a specific McLean metric... away from the 24 singular fibers the K3 looks like tiny flat 2-tori collapsing over S^2
thank you this is a really cool maths fact
does anyone here like flowers?
dead chat
Yes!

guh this seems like a nice article except this typesetting, i hate when they squish things like that 
technically I'm not studying, but I am a Malaysian, yes
NO
Idk being a teacher is pretty pro thing to do
am nub
Lies
you are pro , you're able to progress very fast 
I've been stuck in chp1 of abbott for four months :|
Try 3 sections in a year, you're fast 
am still bad! 
Nope 
me here for 16 months, haven't tried to go further in a while, but you're doing better than we are
guarantee you I'm not if you peek into our threads.
Math teacher?
music teacher first and foremost, STEM teacher on the side
Cool
<@&268886789983436800>
grrrrrr



I'm in the thread and yes you're good
a teacher in school? 
guys i have to pick between lie groups and matrix operations next semester which should i take
Are you trolling?
take neither, do geometric calculus instead
I'm guessing "matrix operations" isn't basic linear algebra but rather something more advanced? Like numerical analysis?
not really
I feel like lie theory is analogous to Fourier theory in the sense that you pick up most of the bits you’d be interested in while in other classes.
Pick linear algebraic forms.
Hii
hi
Hi
Hi
hi
I don't like that
Seems like a lazy way to get around the page limit
btw what made you think I was a good teacher lol
i see people spam that
BNUYY AND KITTY
I can't believe no one pinged me for this banger
Considering the username, I think so because they're certifiably "clashing" random subjects together
Thanks!
yes you are
You have geern role, that's how it works
no I bad, special case
I see. I'll report this to the council of green, the algorithm must be perfected.

no one did it because everyone knows that you will be pinged automatically whenever geometric algebra is mentioned
thought you were talking about number fields
i see, this explains why you appeared. it seems that you got pinged 
Hello?
don't ask to ask, ask your question directly please
@fresh comet can we dm and I tell you about bad discord user who sometimes join to troll server?
I'm your fan, ur creator of k theory,respond my dm
how is this formatting allowed lol
polyhedra though 👀
:3
:3
no
I wanted to ask you about sequences but ig its a little too late 

oh u here 
allright, so I'll define a a sequence A in two parts: 1 is the initial conditions and 2 is the iterated part
Let 'a' be a sequence with terms $a_0,a_1...a_k$
Yeatte
and let A be the sequence where A_n = a_n for $0\leq n \leq k$
Yeatte
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
now let any term greater than k be defined as such
or rather, have the bound
$A_{m+1}\leq A_m + f(\prod_{n=1}^{m}{(1-\frac{1}{A_n})^{-1}})$
Yeatte
I mean for this to essentially mimic primes and to get the lowest expected prime number, but I realized i didn't know enough about this the thing i set up, so I was wondering a few things about this sorta thing
a few things i noticed was
suppose I have A_0 = B_0, and A_1 > B_1
and suppose the two f's are the same for each, and certain conditions liks a>b implies f(a) > f(b)
then the entire f term for the A sequence is less than the entire f term for the B sequence,
so in other words
A_1 > B_1 implies A_2 - A_1 < B_2 - B_1
in a sense balancing it out, maybe? my naiive guess was that any two sequences defined in this manner will have the same growth rate
or rather, $\lim_{x\to\infty}{\frac{A_x}{B_x}} = 1 \forall A,B$
Yeatte
no i literally have no idea what you are trying to do

oh i think i missed a condition, in the thing above i had A_m+1 <= A_m stuff, but in the growth rate conjecture i want it to be A_m+1 = A_m + f stuff
anyway, ill go get an example of what im thinking of
the reason, is that when i made this to make a fake prime sequence, it seemed to have the same growth rate as the actual prime sequence
so i wanted to use this to bound the real primes
you seem to be interested in these things a lot huh
why not read Apostol's analytic number theory?
oo ill write dat down
dis?
yes
huh
turns out oeis does have that fake prime sequence in it
and i got this link
many such cases
rip i guess i wasnt the first to attempt this method
i mean it's fine
it means they prob have results on it
49 bucks to get a pdf? wot
ig ye my only questions were about that sequence thing
well, there is one, but i def dont have the prerequisites to understand the answer to it
Hi wanna chat dm?
Analytic Number Theory is what exactly?
hell divers?
silksong
What'd @neat lintel do now?
MATHEMATICS!!
Why 
they know what they did
yo guys
anyone applying to sumac
Whatis this harassment
Hmm
seems I will have to drop the idea of passing Real Analysis this semester
lemme save my other papers then
Hey
Hey! I am fresher. Can anyone give me guidance for maths for learning Machine learning
Alguém br!?
The integrals and answers can be found at https://math.mit.edu/~yyao1/pdf/2026_finals.pdf
Playlist for the full event: https://www.youtube.com/playlist?list=PLL2kM_tcSHFpIyu21Nb_PNtvdVDKSeqtz
Integration Bee website: https://bit.ly/mitintbee
0:00 Introduction
2:00 Problem 1
8:00 Problem 2
14:10 Problem 3
21:20 Problem 4
27:00 Problem 5
for those interested
😭
did you add the wise man
Boi 67 so tuff
are we deadass
Boi
<@&268886789983436800> wise man is back

this has been addressed.
You may like these two as well
The Iwaniec--Kowalski is like a bible, and the Bateman--Diamond is lesser known but very cool
Also there's always Keith Conrad's lecture notes on the many topics of ANT
My lecture last week on “Teaching Real Analysis as a Video Game” (in the Lean Together conference) is now posted: https://t.co/NS0GHi20dj
Oh wow those covers are so good
Really pretty
whos recommendation holds more weight 
ends the talk with "I actually think we should stop doing that [natural language proofs]" is an insane conclusion to the experiment
"Moreover I am of the opinion that Carthage should be destroyed"
carthago delenda est 🗣️
broke: we should formalize all mathematics with a computer because god forbid we ever make a mistake
woke: we should skip proving half of anything so that we can catch up to the star trek era math that physics people are doing
I'm tired of waiting we need to accellerate
@torpid bay So, silly math we did does cool things with path integrations. Also, Sum and Products (SP) seem impossible to escape from for path based stuff.
hm
would taking different paths for a path integral yeild different inverses? and so a multivalued inverse can be done that way ig
Basically for calculus over C the input function must be g(x)^{2} for it to be the identity, and the function g(x) must be \int^{\infty}_{\infty} g(z)^{2} dz < \infty. Which looks a lot like some properties of physics.
ah, schwartz function iirc
I think someone (sharp) here was nerding out about those the other day. But not really.
I used it to integrate the path function actually. The inverse path would just swap stuff.
Like it'd be pretty simple to do I think.
I'm just not sure if one needs to fractional integrate the path or like derivate the path at all. More so this is just interesting rather than useful feeling to me.

Besides just giving intuition for basic lemmas in quantum physics. I don't feel like it offers much, but it's neat to be able to do.
What's new with your math stuff?
well
I wanted an upper bound for primes
and i based it off of factorization
heere's the basic idea
if i have two consecutive numbers, then at least one of them is not divisible by 2
therefore
either 2+1 or 2+2 is the next prime
however, what if i have the primes 2 and 3? then wahts the chance a number is divisible by neither of them?
$(1-\frac{1}{2})(1-\frac{1}{3})$
Yeatte
which is just (1/2)(2/3) = 1/3
so i take x * (1/3)= 1 where x is to be the number of consecutive numbers to check at most
which if actually calculated, checks out
so x = 3
therefore 3 + 1, 3+2, or 3+3 is prime
and i continue
(1-1/2)(1-1/3)(1-1/5) = (1/3)(4/5), so x = 15/4 = 3.75, but i round x up to 4
so 5 +1,5+2,5+3,5+4 at least one is prime
and we continue
what if we take the worst case scenario where the next predicted prime is that p + x value?
then instead when we start at 2, we get a certain sqeuence
2,4,7,11,15,19...
if I am to write this out using notation it is
$p_{k+1} \leq p_k + \ceil{\prod_{n=1}^{k}{(1-\frac{1}{p_n})^{-1}}}$
Yeatte
but in this case we just set it equal for A_k+1 = A_k + ceil(stuff)
so the question is, how bad of an approximation is it?
if we label this sequence of fake primes as A_k
then from desmos testing
$\lim_{k\to\infty}{\frac{A_k}{p_k}} = 1$
Yeatte
why is 16 in set p?
P U {16}
How did you calculate P? I'm assuming it means primes, btw.
essentailly, compare number n against primes via modulo
if no factors, then add to list
ugh
lets just make 16 prime or smthn
huh
for some reason it listed 16 and 49 in it as well
Na, It's like 2 minuets and some regex in note pad to make
Just take that then come back.
I wanted an efficient algorithm that spits out primes at will :\
🤷♂️
Gotta make sure prime times prime isn't like (x*x = p or p mod x)\
oh crap
for the prime numbers, i didnt actually reset the prime i was using against n

wait, why would that affect this then?
Idk what is 7*7 mod 7?
0
Yeah so, the off chance a number is p*p*... may not be caught by the seive?
7^k mod 7 = 0 for positive integer k, so it should be fine i think
for some reason, it just isn't checking 16/2
like

What would you rather talk about nG?
ye, but the checker value starts at 2
???
3 is the initial number wher i ask "check dis" and p[0] should be the first number it uses in the modulo against it
just add in the if statement if( n mod 2 == 1 && ...) and call it a day?
but for 8 it actaully does check 2, but for 9 it doesnt
wait
hold on
this might be stupid
no nvm i dont get it
yeah its just not running that first prime p[0] sometimes
wait
hold on
int p[] = new int[5000];
void setup() {
p[0] = 2;
p[1] = 3;
int ptr = 2;
for (int n = 5; ptr < 5000; n += 2) {
for (int k=1; k < ptr; k++) {
if (n % p[k] == 0) {
p[ptr] = n;
ptr++;
break;
}
}
}
}
yeah
that'll work as well
maybe its because i'm trying to change b while its in it's own for iteration?
maybe
that makes it hard to reason at least, i try to not modify the looping variable
oh hold on
i see what's going on
aha
yeah it is
so what;s happening is if its not prime, then i set b = 0, but at the end of the for statement, it increases by 1, so i end up cheking all primes greater than 2
and skipping it
another way is to recall that the 5000th prime is larger than 5000(ln 5000 + ln ln 5000 - 1) ~ 48926
make an array of size 48230 for safety, and do a sieve of eratosthenes
ok yeah that fixed it
b = -1 now
fun little problem lel
im glad 49 turned out to not exist
So how does your prime thing look now in desmos?
what is your S and P
Guys, if anyone is from the quant sector, can they please dm me? I need some help 🙂
What's a true prime?
2,3,5 etc
tbh i asked for dms cause i thought this is for pure math
same as a prime
Okay what's a fake prime?
1
That was settled much before, but true prime is still used to refer to the set of prime numbers such that x > 1
one defined by the recurrence relation: $S_{k+1} = S_k + \ceil{\prod_{n=1}^{k}{(1-\frac{1}{p_n})^{-1}}}$
Yeatte
tho this does lead to the generalization of
$A_{k+1} \leq A_k + f({\prod_{n=1}^{k}{(1-\frac{1}{p_n})^{-1}})$
Yeatte
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
Is this a true prime though?
Isn't this a formula that builds a sequence using the usual prime numbers to study their overall distribution?
Can you tell me the problem? I am lost
yep
take 2 consecustive numbers, at least one of them is coprime to 2
at least and exactly one of them to be precise
if i take 3 consecutive numbers, then 2 of them are coprime to 2
but then one of those 2 is coprime to 2
so if i want a number coprime to 2 and 3, then i need just 3 consecutive numbers and itll be in there
so i take 3, and so the next prime after 3 is either 3+1,3+2, or 3+3
going back, the next prime after 2 is either 2+1 or 2+2
-# Might be a miscommunication, but I meant the what the question that you were trying to solve was, but please, if im wrong, go on.
your logic has a flaw though
there is an assumption ye
Among any
𝑘
consecutive numbers, some will be coprime to a given set of primes, but being coprime to small primes does not guarantee being prime, only that the number avoids those factors.
im not checking any random k numbers tho
just the k numbers right above the primes we already have
so no room for any extra possible primes betwene the known primes and the possible set of k numbers we're checking
it should still fail if im correct
please wait
\textbf{Claim.}
Let $p_k$ be the $k$-th prime. There is no guarantee that the interval
[
p_k+1,, p_k+2,, \dots,, p_k+k
]
contains a prime.
\textbf{Proof.}
Fix $k \ge 1$. Choose $k$ distinct primes
$q_1, q_2, \dots, q_k$ such that $q_i > p_k$ for all $i$.
We know that by the Chinese Remainder Theorem, there exists an integer $N$ such that
[
N \equiv -i \pmod{q_i} \quad \text{for } i=1,2,\dots,k.
]
Then for each $i$,
[
N+i \equiv 0 \pmod{q_i},
]
so $N+i$ is composite.
Thus the $k$ consecutive integers
[
N+1, N+2, \dots, N+k
]
are all composite.
Let $p_k$ be the largest prime less than $N$. Then the interval
[
{p_k+1, \dots, p_k+k}
]
contains no prime.
\qed
diddy_lovesme
@torpid bay
oh...
Can you please give me the formal question again then?
Sorry but english isnt my mother language so I have dificulties
I usually do math in my language so theres a boundary
if I have the first k primes, what is the most number of consectuvies numbers above p_k that one has to check to get a new prime? naiively a basic upper bound would be 2^k, tho instead i use actual factorization to cut that down
from what i understand, your intuition is each known prime removes residue classes, so after finitely many steps something must survive
(1-1/2)(1-1/3)(1-1/5)...(1-1/p_k) * x => 1, smallest integer x is the new upper bound of number of consecutive numbers to check above p_k, being the numbers p_k + 1, p_k + 2.. p_k + x
Am I correct?
A residue class (or congruence class) is a set of integers that all share the same remainder when divided by a specific positive integer (n), known as the modulus
diddy_lovesme
so is it still a yes?
removing the residue classes of 0 with respect to each prime modulo yeah
Oh then I guess I see where you went wrong
please wait
The error was:
\textbf{Error.}
The argument incorrectly replaces the statement
[
\text{expected number of survivors } \ge 1'' \] with \[ \text{a prime must exist.''}
]
The product only controls divisibility by primes $\le p_k$, not
compositeness by larger primes.
diddy_lovesme
Formally,
well that statement in itself is true
but it still doesnt account for your logical gap
no?
\begin{theorem}
Let $p_k$ be the $k$-th prime.
The fact that every prime divisor larger than $p_k$ is a new prime does not
imply that an integer coprime to all primes $\le p_k$ is itself prime.
\end{theorem}
\begin{proof}
Suppose $n$ satisfies
[
\gcd(n, p_1 p_2 \cdots p_k) = 1.
]
Then no prime $p \le p_k$ divides $n$. Consequently, every prime divisor of
$n$ is strictly larger than $p_k$, and hence is a new prime.
However, this does not imply that $n$ has only one prime divisor.
Indeed, let
[
n = p_{k+1} \cdot p_{k+2}.
]
Then $n$ is composite, yet all of its prime divisors exceed $p_k$.
Thus $n$ is coprime to all primes $\le p_k$ but is not prime.
Therefore, the implication
[
\gcd(n, p_1 p_2 \cdots p_k)=1 ;\Longrightarrow; n \text{ is prime}
]
is false.
\end{proof}
diddy_lovesme
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Thanks for also talking about your prime function, btw.
It's really neat!
I'm not saying that an number coprime to all p: 2 <= p <= p_k is necessarily a prime, what im saying is that within the interval p_k... p_k + x, if there was a number corpime to p_k etc, then it would either a: be a new prime, or b: be a composite that is divisible by a new prime that would still be in that interval from p_k to p_k + x
and this is with the condition that our p_1 ... p_k list is entirely complete up to the point of p_k at that point
\begin{theorem}
Let $p_k$ be the $k$-th prime and let $x \ge 1$.
The existence of an integer
[
n \in (p_k,; p_k+x]
\quad\text{with}\quad
\gcd(n, p_1p_2\cdots p_k)=1
]
does \emph{not} imply that there exists a new prime in the interval
$(p_k,; p_k+x]$.
\end{theorem}
\begin{proof}
Assume, for contradiction, that the existence of such an $n$ forces a new
prime $q$ with
[
p_k < q \le p_k+x.
]
Choose a prime $Q$ such that
[
Q > p_k + x.
]
(Such a prime exists by Euclid’s theorem.)
Let
[
n := Q^2.
]
Then the following hold:
\begin{enumerate}
\item $n$ is composite.
\item Every prime divisor of $n$ equals $Q$, so all prime divisors of $n$
satisfy $Q > p_k$.
\item Hence
[
\gcd(n, p_1p_2\cdots p_k)=1.
]
\end{enumerate}
Thus $n$ is coprime to all primes $\le p_k$ and is a valid “survivor” of the
small-prime sieve.
However, $n$ has no prime divisor $q$ with
[
p_k < q \le p_k+x,
]
since its only prime divisor is $Q > p_k+x$.
Therefore, the existence of such an $n$ does not force the existence of a new
prime in the interval $(p_k,; p_k+x]$, contradicting the assumption.
Hence the claim is false.
\end{proof}
diddy_lovesme
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I dont know mate I might be heavily misunderstanding
Sorry if I am wrong in this regard
please, do consider better help than me if I dont seem to be understanding what you mean
if Q > p_k + x, then its entirely outside the interval we care about
holy shit i never seem to understand questions
Wait ill really rack my brain
Ohhhhh
OHHHH
That makes much more sense now
😭
sorry for not understanding your question
nah its fine 
specifically i chose x large enough to make sure that 100% there be a comprime within the interval right above p_k
can you give me your full statements will all restraints ill need to consider? I am very bad at keeping things in mind. I need it all laid out for me, if you dont mind
all irght
and the method (formula) you use now
Given the set of primes ${2,3...p_k}$(complete set from 2 to $p_k$, no gaps), there will always exist at least one prime within the interval of consecutive numbers ${p_k+1...p_k+x}$ that is coprime to all prime in that set, and thus is either a new prime, or is a composite divisible by a new prime larger than $p_k$ and is also thus in the interval. $x \coloneq \ceil{\prod_{n=1}^{k}{(1-\frac{1}{p_n})^{-1}}$
Yeatte
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Given the set of primes
[
{2, 3, \dots, p_k} \quad (\text{the complete set of primes from } 2 \text{ to } p_k),
]
there will always exist at least one number in the interval
[
{p_k+1, p_k+2, \dots, p_k+x}
]
that is coprime to all primes in that set. Such a number is either:
\begin{enumerate}
\item a new prime, or
\item a composite divisible by a prime larger than (p_k), which must also lie within the interval.
\end{enumerate}
Here,
[
x \coloneqq \Bigg\lceil \prod_{n=1}^{k} \Big(1 - \frac{1}{p_n}\Big)^{-1} \Bigg\rceil.
]
diddy_lovesme
unless im forgetting anything, that's all
okkkk
should give the minimal x that still guarantees a coprime within interval
so you want to prove this claim rgiht?
yep

can you check it for the set {2,3,5,7}?
then x = 4, and so we check 7+1, 7+2, 7+3, 7+4
see?
7+4 = 11
oh there exists at least one?
yep
Im retarted
Integral from 0 to pi over 2 to ( x * cos (x) - sin (x) ) / (x^2 + sin^2 (x) )
23 is also interesting
first gap of 6 and works a ok
quite trivially, the x will increase without bound
that 8 to 11 interval is probably the closest it has to failing
ooo 113 to 127 gap is also quite close
tho actually, there does become this problem that i thought i might into
where it actuall fails
so yeah 113 to 127 fils
and im pretty sure i know why
I conjecture the statement is likely TRUE, but a rigorous proof is beyond the scope of elementary number theory
\begin{theorem}
Let
[
S_k = {p_1, p_2, \dots, p_k}
]
be the first $k$ primes, and define
[
x = \left\lceil \prod_{i=1}^{k} \left(1 - \frac{1}{p_i}\right)^{-1} \right\rceil.
]
Then there exists at least one integer
[
n \in [p_k+1, p_k+x]
]
such that
[
\gcd(n, p_1 p_2 \cdots p_k) = 1.
]
\end{theorem}
\begin{proof}
Let
[
I = [p_k+1, p_k+x]
]
and for each $i = 1, \dots, k$ define
[
A_i = { n \in I : p_i \mid n }.
]
We want to show
[
|I \setminus \bigcup_{i=1}^k A_i| \geq 1.
]
By the inclusion-exclusion principle:
[
|I \setminus \bigcup_{i=1}^k A_i| = x - \left| \bigcup_{i=1}^k A_i \right|.
]
Using the Möbius function $\mu$:
[
|I \setminus \bigcup_{i=1}^k A_i| = \sum_{d \mid N} \mu(d)
\left( \left\lfloor \frac{p_k+x}{d} \right\rfloor - \left\lfloor \frac{p_k}{d} \right\rfloor \right),
]
where $N = \prod_{i=1}^k p_i$.
Write
[
\left\lfloor \frac{p_k+x}{d} \right\rfloor - \left\lfloor \frac{p_k}{d} \right\rfloor = \frac{x}{d} + \epsilon_d, \quad |\epsilon_d| \le 1.
]
Thus
[
|I \setminus \bigcup_{i=1}^k A_i| = x \sum_{d \mid N} \frac{\mu(d)}{d} + \sum_{d \mid N} \mu(d) \epsilon_d.
]
Observe that
[
\sum_{d \mid N} \frac{\mu(d)}{d} = \prod_{i=1}^k \left( 1 - \frac{1}{p_i} \right) = \frac{1}{x - \epsilon_x}, \quad 0 \le \epsilon_x < 1.
]
Also,
[
\left| \sum_{d \mid N} \mu(d) \epsilon_d \right| \le \sum_{d \mid N} |\mu(d)| = 2^k.
]
Therefore,
[
|I \setminus \bigcup_{i=1}^k A_i| = \frac{x}{x - \epsilon_x} + O(2^k).
]
Since the error term $O(2^k)$ dominates for large $k$, this bound is insufficient to guarantee $|I \setminus \bigcup_{i=1}^k A_i| \ge 1$ rigorously.
Nonetheless, for small $k$, the main term exceeds 1 and the bound $x$ ensures that at least one integer in $I$ is coprime to all $p_i$.
\end{proof}
diddy_lovesme
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before i go to eat, can you run a test for k = 30?
i think it fails for 113
def sieve(limit):
is_prime = [True] * (limit + 1)
is_prime[0] = is_prime[1] = False
for i in range(2, int(math.sqrt(limit)) + 1):
if is_prime[i]:
for j in range(i*i, limit + 1, i):
is_prime[j] = False
return [i for i in range(2, limit + 1) if is_prime[i]]
primes = sieve(200)[:30] # First 30 primes
product = 1.0
for p in primes:
product *= p / (p - 1)
x = math.ceil(product)
print(f"x = {x}")
# Check interval [114, 122]
for n in range(114, 123):
factors = []
temp = n
for p in primes:
if temp % p == 0:
factors.append(p)
while temp % p == 0:
temp //= p
print(f"{n} has factors in S_30: {factors}")
it failed this but idk if i did smth bad in code
the x for 113 is about 8.7, but the gap from 113 to 127 is 14
and i think the propblem is multiplying the fractions together
Hey guys
I have a question regarding cantor’s theorem
If a set led to a set of all sets e.g. the set necessarily N turned to a self-referential set of all sets, would that mean the set necessarily N is contradictory not only that it’s improperly formatted?
e.g., a necessary disjunction of all insufficient explanations Z where Z in itself is an explanation and is found in itself and every other set L is found in Z and is an insufficient explanation.
hm
yeah it must be the fractions
then the true x must be between $\ceil{\prod_{n=1}^{k}{(1-\frac{1}{p_n})^{-1}}}$ and $\prod_{n=1}^{k}{\ceil{(1-\frac{1}{p_n})^{-1}}}$
Yeatte
the latter just equals 2^k
the question is, whats the minimal number of primes where i need to switch the inside to ceil and keep the rest having the ceil on the outside
actually, why does it fail?
halo
all check later kay
I have my own homework now
but a very fun problem man
then floor(x/2) is minimal number of numbers divisible by 2, same for floor(x/p) for prime p, the thing is, if i do floor(floor(x/2)/3) then im that gets the true value for number of minimal primes in that interval, but floor(x/6) does not
been a long time since i had to use python for proving
yeah, x was a little lowballed because i didnt account for that
oop
a better example
yeah, this fracion error occurs much more in higher numbers
the true x should be higher because these are lower
mm
well, onthe other hand
kinda feels like p_k <= p_(k+1) <= 2p_k is in sight
eh
YWNBAW
\documentclass{article}
\usepackage{amsmath, amssymb}
\begin{document}
\section*{Backpropagation Mathematical Model}
\subsection*{1. Forward Pass}
For a network with $L$ layers:
[
a^{[0]} = x
]
[
z^{[l]} = W^{[l]} a^{[l-1]} + b^{[l]}, \quad l = 1, 2, ..., L
]
[
a^{[l]} = \sigma^{[l]}(z^{[l]}), \quad l = 1, 2, ..., L
]
where
\begin{itemize}
\item $W^{[l]}$ is the weight matrix of layer $l$
\item $b^{[l]}$ is the bias vector of layer $l$
\item $\sigma^{[l]}$ is the activation function
\end{itemize}
The final output is:
[
\hat{y} = a^{[L]}
]
\subsection*{2. Loss Function}
Let the loss function be $L(\hat{y}, y)$, e.g.:
[
L = \frac{1}{2} (\hat{y} - y)^2 \quad \text{(MSE)}
]
or
[
L = -\sum y \log(\hat{y}) \quad \text{(cross-entropy)}
]
\subsection*{3. Backward Pass – Error Terms}
Define the error term $\delta^{[l]}$:
[
\delta^{[l]} = \frac{\partial L}{\partial z^{[l]}} = \frac{\partial L}{\partial a^{[l]}} \odot \sigma'^{[l]}(z^{[l]})
]
\textbf{Output layer:}
[
\delta^{[L]} = \nabla_{a^{[L]}} L \odot \sigma'^{[L]}(z^{[L]})
]
\textbf{Hidden layers ($l = L-1, ..., 1$):}
[
\delta^{[l]} = (W^{[l+1]})^T \delta^{[l+1]} \odot \sigma'^{[l]}(z^{[l]})
]
\subsection*{4. Gradients of Weights and Biases}
[
\frac{\partial L}{\partial W^{[l]}} = \delta^{[l]} (a^{[l-1]})^T
]
[
\frac{\partial L}{\partial b^{[l]}} = \delta^{[l]}
]
\subsection*{5. Weight Update (Gradient Descent)}
[
W^{[l]} \gets W^{[l]} - \eta \frac{\partial L}{\partial W^{[l]}}
]
[
b^{[l]} \gets b^{[l]} - \eta \frac{\partial L}{\partial b^{[l]}}
]
where $\eta$ is the learning rate.
\end{document}
diddy_lovesme
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\documentclass{article}
\usepackage{amsmath}
\begin{document}
\section*{Why We Take the Derivative of the Sigmoid Function}
The sigmoid function is defined as:
[
\sigma(x) = \frac{1}{1 + e^{-x}}
]
During backpropagation, we want to update the weights of a neural network to reduce the loss. To do this, we need to know how the loss changes with respect to each weight. Using the chain rule, for a weight $w$ connected to a neuron, we have:
[
\frac{\partial L}{\partial w} = \frac{\partial L}{\partial y_{\text{hat}}} \cdot \frac{\partial y_{\text{hat}}}{\partial a} \cdot \frac{\partial a}{\partial z} \cdot \frac{\partial z}{\partial w}
]
Here:
\begin{itemize}
\item $z = w \cdot x + b$ is the input to the neuron,
\item $a = \sigma(z)$ is the output (activation) of the neuron,
\item $y_{\text{hat}}$ is the output of the network,
\item $L$ is the loss function.
\end{itemize}
The term $\frac{\partial a}{\partial z}$ is the derivative of the sigmoid function:
[
\sigma'(z) = \sigma(z) (1 - \sigma(z))
]
\subsection*{Intuition}
\begin{itemize}
\item The derivative measures \textbf{how sensitive the neuron's output is to changes in its input}.
\item If the output $a$ is near 0 or 1, the derivative is small, meaning the neuron is \textbf{already confident}, so its weight should change less.
\item If $a$ is around 0.5, the derivative is larger, meaning small changes in input affect the output more, so the weight should adjust more.
\item Multiplying the error by $\sigma'(z)$ correctly scales the weight update for each neuron.
\end{itemize}
\end{document}
diddy_lovesme
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@molten grove is it ok for me to dm you? (to talk about the thing in your bio)
Sure
what the blud
There should be
Mannn
be feather, do idiot things that'll hurt your career
get stressed when you potentially have to face the consequences of said idiot things
Professor I want to do research with is ASKING ME FOR MY TRANSCRIPT and it DOES NOT LOOK THE BEST 😐
He likes me but still
😔
A
Noo
heyyy does anybody by chacne have studydrive premium?
ahh don't be a spoilsport
we all need to blurt out thinking
especially in mathematical situations where instant resolve is needed
slowmode just delays things
and to be honest only profound mental deficiency would cause someone to spam here
precisely, gives people a chance to think longer before hitting "send"
I can't think of any tactful reply to this
haha fair
i agree
And then someone sends a wall of text halway through and following the convo becomes impossible

likely spammer
ik
Then why say it
idk its just funny and unusual
also it says spammer not scammer
and ur status says scammer
is 1/infinity in an rng still possible
What does "possible" mean here? And what does "in an rng" mean here?
well 1 doesnt exist in a rng
well rings are also rngs but not every rng is a ring
honestly when someone says rng i automatically assume they specifically dont want 1 in there
tho ur still right ofc
<@&268886789983436800> is this allowed 
Nope

indeed, PDA in a starbucks is not allowed

Why would they do this…
what about 67?
I know the quadratic field with discriminant d=-67 is an example of a non euclidean ring of integer
rizz sigma skibidi ohio
go to sleep
This app keeps sending me side quests instead of the main story.
most game have more side quest than main story ¯_(ツ)_/¯
GUYS HAS ANYONE QUALIFIED RMO?
<@&268886789983436800> was my postgrad refused or did i accidentally select undergrad
Send your queries to modmail
Hi
I'm preparing for ioqm
Finally found someone
Hmm
I wonder how my fellow math lovers cope with crippling depression
I am unable to focus
See psychiatrist
Smh
Take a break
the number 2
secret ,
One marriage had generated the world around us
from who they made natural numbers
the number 2 for couples .male and female in humans ,plants ,animals .
Yoo
Yoyoyoyo
@azure rune @charred wigeon
Hi, new nerds! welcome to #discussion, home of general/non-mathematical discussion. We also have #math-discussion for more mathematically-oriented discussion


Hi
@vivid halo Before the chat got server political. I assume that Artin Stacks add new properties that Orbifolds don't have, due to their continuity?
they allow for much more general quotients among other things
like here is something funny this allows: a quotient X/G should have dimension dim(X/G)=dim(X)-dim(G), and this dimension will be negative as soon as dim(G)>dim(X)
finite groups have dimension 0 so no negative dimensional examples arise for Deligne-Mumford stacks, but plenty of more general Artin stacks are like this
maybe the most basic example is BG=pt/G
Dimension like literal dimension or?
any good definition of dimension will have to be like this yes
it's either that or you just give up being able to define dimension for stacks which is the worse alternative
R^{-1} sounds wild.
it's not quite like that though
for stacks individual points sort of remember their "internal symmetries" and if this internal group of symmetries has positive dimension then this should modify the overall dimension accordingly
when dim(G)<dim(X) this is a very classical thing that people are comfortable with
already taking pt/R is simple enough
what's pt?
point
Okay keeep going?
a nice example which is endlessly useful in practice is to consider a quotient like C/C* where C* acts by the obvious multiplication action on C
the resulting quotient has two points: one is the quotient C*/C*=pt which is a classical point with no internal symmetries, one is the quotient {0}/C*=pt/C* which is a stacky point with internal symmetries C*
this stack is incredibly useful when you consider vector bundles over it
a vector bundle over the quotient C*/C*=pt is just a vector space of course
a vector bundle over the quotient {0}/C*=pt/C* turns out to be a graded vector space V=\oplus_{n\in Z}V_n
a vector bundle over the quotient C*/C*=pt turns out to be a filtered vector space (...\subseteq F^{-1}V\subseteq F^0V\subseteq F^1V\subseteq...)
how to see this intuitively?
now everything in terms of filtered and graded vector spaces can be interpreted in terms of geometry over this quotient stack
pt/C* calculus type thing, or what?
the general explanation for this is Cartier duality which is a bit overkill for this example but in those terms it is because BS^1 is Cartier dual to Z
yeah hold on lol
I mean here the observation is just that a vector bundle on BC*=pt/C* is the same thing as a C-linear representation of C*
such a representation V splits into a direct sum of eigenspaces V_n for this C*-action where V_n is the subspace upon which z in C* acts by multiplication by z^n
if you have a filtered vector space then both the underlying vector space and the associated graded vector space are recovered by just pulling this vector bundle back to either of these two points
how can i see this without knowing about classifying spaces?

