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%I #5 Apr 13 2012 15:05:14
%S 4,8,7,9,10,6,14,8,18,16,9,21,20,8,8,25,22,11,26,45,34,4,28,3,32,39,
%T 10,8,38,65,24,8,50,3,40,5,57,44,61,8,26,46,12,12,50,121,8,23,61,52,
%U 22,23,19,37,49,24,49,58,62,6,97,67,55,11,14,165,68,57,9
%N Smallest base b for which A181780(n) is a Fermat pseudoprime.
%C That is, the smallest b for which b^(s-1) = 1 (mod s), where s is in A181780.
%H T. D. Noe, <a href="/A211456/b211456.txt">Table of n, a(n) for n = 1..10000</a>
%t 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}]]]]; First/@Transpose[t][[3]]
%Y Cf. A181780, A211455, A211457, A211458.
%K nonn
%O 1,1
%A _T. D. Noe_, Apr 13 2012