Question 3
An $n$-string is a string of digits formed by writing the numbers $1, 2, \ldots, n$ in some order (in base ten). For example, one possible 10-string is
35728910461
What is the smallest $n \gt 1$ such that there exists a palindromic $n$-string?
35728910461
What is the smallest $n \gt 1$ such that there exists a palindromic $n$-string?