%I #20 Aug 04 2021 14:28:07
%S 15,51,65,85,87,145,221,255,377,435,451,493,561,595,703,1015,1105,
%T 1479,1729,1885,1891,2091,2465,2755,2821,2845,3091,3451,4033,5365,
%U 5685,6409,6601,7395,7397,7483,7701,8695,8911,9061,9673,10585,10991,11041,11305
%N Pseudoprimes to base 86.
%C Composite numbers n such that 86^(n-1) == 1 (mod n). - _Michel Lagneau_, Feb 18 2012
%H T. D. Noe, <a href="/A020214/b020214.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 = 86; 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],CompositeQ[#]&&PowerMod[86,#-1,#]==1&] (* _Harvey P. Dale_, Aug 04 2021 *)
%Y Cf. A001567 (pseudoprimes to base 2).
%K nonn
%O 1,1
%A _David W. Wilson_