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 A255203 #9 Mar 07 2015 15:32:39 %S A255203 2,3,5,7,13,17,19,23,31,41,47,53,61,67,73,83,89,101,107,139,149,157, %T A255203 167,173,179,193,227,239,251,271,277,311,317,337,383,389,409,431,443, %U A255203 457,467,479,491,503,541,569,587,593,613,643,677,683,691,709,719,733 %N A255203 Primes p for which no bases b with 1 < b < p exist such that p is a base b Wieferich prime. %C A255203 p = prime(n) such that A242830(n) = 0. %o A255203 (PARI) forprime(p=1, , b=2; i=0; while(b < p, if(Mod(b, p^2)^(p-1)==1, i++); b++); if(i==0, print1(p, ", "))) %Y A255203 Cf. A255204, A255205, A255206, A255207, A255208, A255209, A255210. %K A255203 nonn %O A255203 1,1 %A A255203 _Felix Fröhlich_, Feb 17 2015