correct?

[shell dragon]

is the first line the question?

@north sorrel

[wild wharf]

Correct

[near fern]

shouldnt it be -3 instead of -6, of course if only the big O is relevant then 🤷‍♂️

third line from the bottom should have -2×3/2 no?

[near fern]

it calculates to 0+1+2+...+n-1+n

to sum up to n-1, you need (n-1)n/2

i meant

you wanted to remove 1+2 right?

you ended up removing 1+2+3

yeah

if you removed 1+2 it'd be -3 right hahah

no worries

[noble elbow]

Solved

Post marked as solved by @north sorrel.

Use .unsolved if this was a mistake.