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 A274510 #8 Jul 06 2016 00:55:50 %S A274510 0,3,1,7,4,2,4,5,8,15,9,3,5,7,9,4,19,7,10,25,7,6,27,25,10,25,35,23,36, %T A274510 21,22,11,40,33 %N A274510 a(n) is the only number m such that 6^(2^m) + 1 is divisible by A273947(n). %o A274510 (PARI) forstep(p=3, 10^15, 2, if(!Mod(p, 3)==0, if(isprime(p), o=znorder(Mod(6, p)); x=ispower(2*o); if(2^(x-1)==o, print1(x-2, ", "))))); %Y A274510 Cf. A273947. %K A274510 nonn,more %O A274510 1,2 %A A274510 _Arkadiusz Wesolowski_, Jun 25 2016