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 A211457 #5 Apr 13 2012 15:03:46
%S A211457 11,13,18,25,23,29,25,37,31,35,29,34,37,55,57,49,47,51,49,49,43,81,59,
%T A211457 88,61,56,89,97,73,81,91,109,69,118,83,25,68,85,81,125,109,95,131,133,
%U A211457 97,137,145,67,94,107,139,142,150,134,165,151,113,119,121,179
%N A211457 Largest number b for which A181780(n) is a Fermat pseudoprime.
%C A211457 That is, the largest b for which b^(s-1) = 1 (mod s), where s is in A181780.
%H A211457 T. D. Noe, <a href="/A211457/b211457.txt">Table of n, a(n) for n = 1..10000</a>
%t A211457 t = {}; n = 1; While[Length[t] < 100, n++; If[! PrimeQ[n], s = Select[Range[2, n-2], PowerMod[#, n-1, n] == 1 &]; If[s != {}, AppendTo[t, {n, Length[s], s}]]]]; Last/@Transpose[t][[3]]
%Y A211457 Cf. A181780, A211455, A211456, A211458.
%K A211457 nonn
%O A211457 1,1
%A A211457 _T. D. Noe_, Apr 13 2012