A020142 Pseudoprimes to base 14.

15, 39, 65, 195, 481, 561, 781, 793, 841, 985, 1105, 1111, 1541, 1891, 2257, 2465, 2561, 2665, 2743, 3277, 5185, 5713, 6501, 6533, 6541, 7107, 7171, 7449, 7543, 7585, 8321, 9073, 10585, 12403, 12505, 12545, 12805, 12871, 13429, 14111, 14689, 15067, 15457

Offset: 1

Author

David W. Wilson

Keywords

• nonn

Comments

Composite numbers n such that 14^(n-1) == 1 (mod n). - Michel Lagneau, Feb 18 2012

Links

• T. D. Noe, Table of n, a(n) for n = 1..1000
• Index entries for sequences related to pseudoprimes

Crossrefs

Cf. A001567 (pseudoprimes to base 2).

Programs

Maple

select(t -> not isprime(t) and 14 &^ (t-1) mod t = 1, [seq(i,i=3..20000,2)]); # Robert Israel, Jun 12 2018

Mathematica

pseudos14 = {}; n = 1; While[Length[pseudos14] < 100, n++; If[!PrimeQ[n] && PowerMod[14, n - 1, n] == 1, AppendTo[pseudos14, n]]]; pseudos14 (* T. D. Noe, Feb 21 2012 *)