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A020143 Pseudoprimes to base 15. 1
14, 341, 742, 946, 1477, 1541, 1687, 1729, 1891, 1921, 2821, 3133, 3277, 4187, 6541, 6601, 7471, 8701, 8911, 9073, 10279, 10649, 12871, 14041, 14701, 15409, 15841, 16841, 19201, 20017, 24521, 25313, 25546, 28063, 29341, 30889, 31021, 38963, 41041 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Composite numbers n such that 15^(n-1) == 1 (mod n).

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

Index entries for sequences related to pseudoprimes

MATHEMATICA

base = 15; 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 *)

CROSSREFS

Cf. A001567 (pseudoprimes to base 2).

Sequence in context: A278194 A035273 A239783 * A161927 A253457 A239784

Adjacent sequences:  A020140 A020141 A020142 * A020144 A020145 A020146

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified September 22 19:01 EDT 2018. Contains 315270 sequences. (Running on oeis4.)