dense wharf
First I converted the number into the form abccba, which got me 100001a + 10010b + 1100c, but that didn't rly get me anywhere. Then I tried to do the divisibility rule for 1001, which works for 7, 11 and 13. From that, I got abc-cba= 99a - 99c = 99(a-c). Is this in the right direction?
half driftBOT
dense wharf
<@&286206848099549185>
echo canopy
Me personally I’d just factor and “casework”. I think it’s easier that way and I don’t think you’d be able to go towards the answer with your approach
(Like after you get to the expansion just simplify the equation to some number times a + some other number times c == 0 mod 13 since the b term cancels out as you previously stated and then it gets easier)
If you want the answer it’s ||none as the question asks for 3 distinct integers but the a must = c for divisibility by 13 as seen from our equation a + 12c == 0 mod 13 -> a - c == 0 mod 13 -> a == c mod 13 and since they are digits, a = c||