[seqfan] Re: Special primes

[Hans Havermann]

AH: "Have these primes a name?"

RC: "Kamada calls them near-repdigit palindromes... De Geest calls them palindromic wing primes..."

The number AH posted was 252 nines followed by an 8 followed by 253 nines, so 10^506-10^253-1. We can be fairly certain that this is the number that was intended because 1) it is prime and 2) neither palindrome 10^505-10^252-1 nor palindrome 10^507-10^253-1 is prime. Unfortunately, because 10^506-10^51-1 is also prime, it fails to be what I call an aenlic prime (A039986).