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%I #18 Jun 13 2018 09:15:44
%S 15,21,25,33,35,55,75,77,105,165,175,231,265,275,325,385,425,525,545,
%T 561,781,825,949,1105,1113,1155,1325,1369,1417,1491,1541,1749,1785,
%U 1825,1891,1925,2289,2465,2701,2725,2821,3445,3597,3605,4033,4081,4097,4505,4681
%N Pseudoprimes to base 76.
%C Composite numbers n such that 76^(n-1) == 1 (mod n). - _Michel Lagneau_, Feb 18 2012
%H T. D. Noe, <a href="/A020204/b020204.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Ps#pseudoprimes">Index entries for sequences related to pseudoprimes</a>
%t base = 76; t = {}; n = 1; While[Length[t] < 100, n++; If[! PrimeQ[n] && PowerMod[base, n-1, n] == 1, AppendTo[t, n]]]; t (* _T. D. Noe_, Feb 21 2012 *)
%Y Cf. A001567 (pseudoprimes to base 2).
%K nonn
%O 1,1
%A _David W. Wilson_