Every natural number is the sum of forty-nine palindromes (Q2830341)

A palindrome in base \(g\) is a number whose string of base \(g\) digits reads the same from the left and from the right. The ground-breaking paper under review initiates the additive theory of palindromes. The author proves that every positive integer can be expessed as the sum of forty-nine (possibly zero) decimal palindromes. Inspired by Banks' result, an improvement has been obtained. \textit{J. Cilleruelo} et al. [``Every positive integer is a sum of three palindromes'', Math. Comput. 87, No. 314, 3023--3055 (2018; Zbl 1441.11016)] show that the statement in the title holds for every base \(g \geq 5\).