Reciprocal Sum of Palindromes

Phakhinkon Phunphayap, Prapanpong Pongsriiam

A positive integer $n$ is said to be a palindrome in base $b$ (or $b$-adic palindrome) if the representation of $n=(a_k{a}_{k-1}\cdots a_0{)}_b$ in base $b$ with $a_k\ne 0$ has t…