login
Pseudoprimes to base 26.
1

%I #18 Jun 13 2018 09:17:03

%S 9,15,25,27,45,75,133,135,153,175,217,225,259,425,475,561,589,675,703,

%T 775,925,1035,1065,1147,2465,3145,3325,3385,3565,3825,4123,4525,4741,

%U 4921,5041,5425,6093,6475,6525,6601,6697,8029,8695,8911,9073,10585,11005

%N Pseudoprimes to base 26.

%C Composite numbers n such that 26^(n-1) == 1 (mod n). - _Michel Lagneau_, Feb 18 2012

%H T. D. Noe, <a href="/A020154/b020154.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 = 26; 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_