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 A355959 #13 Aug 27 2023 16:42:25 %S A355959 5,45827 %N A355959 Primes p such that (p+2)^(p-1) == 1 (mod p^2). %C A355959 a(3) > 107659373057 if it exists. %C A355959 Primes p such that the Fermat quotient of p base 2 (A007663) is congruent to 1/2 modulo p. - _Max Alekseyev_, Aug 27 2023 %o A355959 (PARI) forprime(p=1, , if(Mod(p+2, p^2)^(p-1)==1, print1(p, ", "))) %Y A355959 (p+k)^(p-1) == 1 (mod p^2): A355960 (k=5), A355961 (k=6), A355962 (k=7), A355963 (k=8), A355964 (k=9), A355965 (k=10). %Y A355959 Cf. A007663. %K A355959 nonn,hard,more,bref %O A355959 1,1 %A A355959 _Felix Fröhlich_, Jul 21 2022