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%I #7 Mar 31 2017 21:35:50
%S 131,191,313,919,113111311,131333131,313111313,331333133,11199199111,
%T 99911911999,1111191911111,9999919199999,133131131131331,
%U 311313313313113,777997999799777,999779777977999,11177771717777111
%N Palindromic primes made of only two digits say a and b such that replacing a with b and vice versa one gets another prime.
%C Conjecture: Sequence is finite.
%e 131 and 313 are both members. 313 is obtained by replacing a 3 with a 1 and a 1 with a 3.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Sep 29 2003
%E More terms from _David Wasserman_, Aug 04 2005