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%I #15 Oct 12 2019 15:43:43
%S 4,22,44,76,133,253,418,436,451,481,638,763,1247,1417,1541,1562,1729,
%T 1771,1891,1981,2047,2059,2071,2356,2398,2737,2821,3053,3289,3553,
%U 4033,4807,4921,5377,5963,6322,6533,6601,6817,7337,8284,8321,8911,9361,10879
%N Pseudoprimes to base 45.
%C Composite numbers n such that 45^(n-1) == 1 (mod n).
%H T. D. Noe, <a href="/A020173/b020173.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 = 45; 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[11000],CompositeQ[#]&&PowerMod[45,#-1,#]==1&] (* _Harvey P. Dale_, Oct 12 2019 *)
%Y Cf. A001567 (pseudoprimes to base 2).
%K nonn
%O 1,1
%A _David W. Wilson_