%I #13 Aug 03 2014 14:01:12
%S 4,6,8,9,12,18,24,36,45,65,72,111,117,185,205,259,276,333,369,481,533,
%T 561,585,703,1105,1221,1441,1517,1665,1729,1845,1891,1921,2047,2405,
%U 2465,2466,2553,2556,2665,2806,2821,3439,4005,4329,4636,4797,5257,5461,5662
%N Pseudoprimes to base 73.
%C Composite numbers n such that 73^(n-1) == 1 (mod n).
%H T. D. Noe, <a href="/A020201/b020201.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 = 73; 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_