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%I #13 Aug 03 2014 14:01:12
%S 6,22,33,49,51,66,85,154,165,187,217,385,561,637,682,703,946,1045,
%T 1078,1105,1309,1519,1705,1729,2047,2209,2245,2465,2701,2805,2821,
%U 3165,3201,3565,4123,4165,4566,4631,4774,5005,5214,5611,5797,6119,6369,6601,7633
%N Pseudoprimes to base 67.
%C Composite numbers n such that 97^(n-1) == 1 (mod n).
%H T. D. Noe, <a href="/A020195/b020195.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 = 67; 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_