%I #15 Aug 03 2014 14:01:12
%S 15,58,87,145,435,451,561,645,946,1015,1105,1141,1247,1541,1661,1729,
%T 1885,1991,2413,2465,2755,2821,3097,4215,4681,4795,5365,5611,5729,
%U 6191,6409,6533,6601,7421,8149,8321,8705,8911,9637,10081,10217,10585,11041
%N Pseudoprimes to base 59.
%C Composite numbers n such that 59^(n-1) == 1 (mod n).
%H R. J. Mathar, <a href="/A020187/b020187.txt">Table of n, a(n) for n=1..1137</a>
%H <a href="/index/Ps#pseudoprimes">Index entries for sequences related to pseudoprimes</a>
%t base = 59; 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 *)
%t Select[Range[12000],!PrimeQ[#]&&PowerMod[59,#-1,#]==1&] (* _Harvey P. Dale_, Oct 02 2012 *)
%Y Cf. A001567 (pseudoprimes to base 2).
%K nonn
%O 1,1
%A _David W. Wilson_