2138312domain: NAppears in sequencesPalindromes whose sum of divisors is odd.at n=21A028984Nonsquare palindromes whose sum of divisors is odd.at n=6A028985a(n) = smallest palindrome k > n such that k/n is a square; a(n) = 0 if no solution exists.at n=7A260726Palindromes that are the sums of consecutive fourth powers.at n=7A265449