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 A230487 #15 Apr 01 2024 02:39:08 %S A230487 4681,29341,42799,49141,52633,85489,90751,104653,253241,280601,458989, %T A230487 580337,1004653,1082401,1207361,1251949,1302451,1678541,1907851, %U A230487 1909001,2419385,2510569,2811271,3090091,3539101,5044033,5049001,5173601,5489641,5590621,7177105 %N A230487 Strong pseudoprimes k to base 2 such that either k-2 or k+2 is prime. %H A230487 Amiram Eldar, <a href="/A230487/b230487.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..5001 from Shyam Sunder Gupta) %e A230487 4681 is a strong pseudoprime (base 2) and 4679 is prime. 253241 is a strong pseudoprime (base 2) and 253243 is prime. %Y A230487 Union of A230483 and A230484. %Y A230487 Cf. A001567, A001262, A230485. %K A230487 nonn %O A230487 1,1 %A A230487 _Shyam Sunder Gupta_, Oct 20 2013