I saw this problem in an old book on combinatorics I had, it took me a while to solve, but it is easy if you are familiar with the work of Euler.
Prove that an even length palindrome of integers is divisible by 11
If you know the answer - post it in the comments. If not, wait for a post by me :)
Prove that an even length palindrome of integers is divisible by 11
If you know the answer - post it in the comments. If not, wait for a post by me :)
