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 A052231 #11 Jun 07 2018 02:55:21 %S A052231 47,73,131,157,257,367,677,971,1097,1123,1181,1543,1601,1753,2383, %T A052231 2441,2467,2677,3307,3407,3617,3727,3911,4357,4457,4903,4987,5113, %U A052231 5297,5381,5407,5743,5801,6037,6373,6977,7187,7213,7481,7717,7817,7901,7927,8053 %N A052231 Primes p from A031924 such that A052180(primepi(p)) = 7. %Y A052231 Cf. A031924, A031925, A052180. %K A052231 nonn %O A052231 1,1 %A A052231 _Labos Elemer_, Feb 01 2000