This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A076613 #4 Mar 31 2012 14:40:00 %S A076613 101,181,191,313,383,787,797,919,10601,11411,12421,12821,13831,13931, %T A076613 15451,16061,16661,17471,17971,18181,18481,19891,19991,30103,30403, %U A076613 30803,31013,32423,34843,35053,35153,38083,38183,70607,71917,73037 %N A076613 Palindromic primes with nonprime middle digit. %e A076613 a(12)=12821 is palindromic prime and its middle digit 8 is not prime, a(13)=13831 is palindromic prime and its middle digit 8 is not prime, a(14)=13931 is palindromic prime and its middle digit 9 is not prime, ... %p A076613 ts_num_midpal := proc(n) local ad,adr,midigit; ad := convert(n,base,10): adr := ListTools[Reverse](ad): if nops(ad) mod 2 = 0 then return 1; fi; midigit := op( (nops(ad)+1)/2,ad ): if (isprime( midigit )='false' and adr=ad) then return 0; else return 1; fi end: ts_pra_n_pal := proc(n) local p1; p1 := ithprime(n): if ts_num_midpal(p1) = 0 then return (p1) fi end: apranpal := [seq(ts_pra_n_pal(i), i=1..100000)]: apranpal; %Y A076613 Cf. A002385, A069217. %K A076613 easy,nonn,base %O A076613 1,1 %A A076613 _Jani Melik_, Oct 21 2002