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 A259502 #15 Dec 06 2015 11:35:53 %S A259502 5,47,151051,240727,911135839 %N A259502 Primes p such that nextprime(p + 1)^(p - 1) == 1 (mod p^2). %C A259502 Nextprime as defined in A007918. %C A259502 These are Wieferich primes p to a prime base q where the difference between p and q has minimal or almost minimal (if the difference between p and the previous prime is smaller) value. %C A259502 No further terms up to 10^9. %o A259502 (PARI) forprime(p=1, , if(Mod(nextprime(p+1), p^2)^(p-1)==1, print1(p, ", "))) %Y A259502 Cf. A001220, A007918, A244546, A260377, A260507. %K A259502 nonn,hard,more %O A259502 1,1 %A A259502 _Felix Fröhlich_, Nov 08 2015