526593domain: NAppears in sequencesa(1)=1. a(n) = the smallest integer > a(n-1) that is an (odd) palindrome when written in binary, and is such that (a(n)-a(n-1))/2 is prime.at n=23A161536Fermat pseudoprimes to base 2 that are octadecagonal.at n=6A322160Fermat pseudoprimes to base 2 that are palindromic in base 2.at n=13A346567