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 A180066 #7 May 13 2013 01:54:11 %S A180066 23,29,37,31,53,7,13,127,157,7,97,5,61,53,149,151,229,137,157,103,43, %T A180066 41,157,233,151,277,13,131,313,277,11,233,157,359,499,13,79,431,5,101, %U A180066 397,661,307,479,313,331,13,251,11,601,103,1093,449,409,733,571,499,673,829 %N A180066 Smallest prime factor of 2-strong pseudoprimes. %H A180066 Charles R Greathouse IV, <a href="/A180066/b180066.txt">Table of n, a(n) for n = 1..10000</a> %H A180066 <a href="/index/Ps#pseudoprimes">Index entries for sequences related to pseudoprimes</a> %F A180066 a(n) = A020639(A001262(n)). %e A180066 The 8th pseudoprime, 42799, is divisible by 127. %K A180066 nonn %O A180066 1,1 %A A180066 Kevin Batista (kevin762401(AT)yahoo.com), Aug 09 2010 %E A180066 b-file and edits from _Charles R Greathouse IV_, Aug 28 2010