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 A215568 #14 Mar 31 2024 02:08:25 %S A215568 1907851,4181921,4469471,5256091,9006401,9863461,14709241,25326001, %T A215568 40987201,55729957,58449847,67194401,94502701,100618933,109437751, %U A215568 114305441,133800661,135969401,147028001,153928133,161304001,192857761,196049701,213035761,226359547,245950561 %N A215568 Strong pseudoprimes to base 2 and 5. %H A215568 Amiram Eldar, <a href="/A215568/b215568.txt">Table of n, a(n) for n = 1..880</a> (terms below 10^12; terms 1..381 from M. F. Hasler) %Y A215568 Intersection of A001262 and A020231. %Y A215568 Cf. A072276, A215566. %K A215568 nonn %O A215568 1,1 %A A215568 _M. F. Hasler_, Aug 16 2012