1,1

Every palindrome with an even number of digits is divisible by 11 (in base 5) and therefore is composite (not prime). Hence there is no palindromic prime with an even number of digits.

Eric Weisstein: Palindromic Prime.

Cf. A029973, A117700.

Sequence in context: A090192 A097331 A094032 this_sequence A155759 A082974 A167635

Adjacent sequences: A117777 A117778 A117779 this_sequence A117781 A117782 A117783

nonn

Martin Renner (martin.renner(AT)gmx.net), Apr 15 2006