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A020151 Pseudoprimes to base 23. 2
22, 33, 91, 154, 165, 169, 265, 341, 385, 451, 481, 553, 561, 638, 946, 1027, 1045, 1065, 1105, 1183, 1271, 1729, 1738, 1749, 2059, 2321, 2465, 2501, 2701, 2821, 2926, 3097, 3445, 4033, 4081, 4345, 4371, 4681, 5005, 5149, 6253, 6369, 6533, 6541, 7189, 7267 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Composite numbers n such that 23^(n-1) == 1 (mod n).

LINKS

R. J. Mathar, Table of n, a(n) for n=1..1085

Index entries for sequences related to pseudoprimes

MATHEMATICA

base = 23; 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: A067087 A155709 A095044 * A071265 A213974 A103320

Adjacent sequences:  A020148 A020149 A020150 * A020152 A020153 A020154

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified October 23 09:28 EDT 2019. Contains 328345 sequences. (Running on oeis4.)