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A020142 Pseudoprimes to base 14. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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

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 *)

CROSSREFS

Cf. A001567 (pseudoprimes to base 2).

Sequence in context: A055131 A121051 A139042 * A146696 A186295 A259429

Adjacent sequences:  A020139 A020140 A020141 * A020143 A020144 A020145

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified November 22 06:06 EST 2018. Contains 317453 sequences. (Running on oeis4.)