A020179 - OEIS

A020179

Pseudoprimes to base 51.

10, 25, 50, 65, 70, 91, 175, 325, 451, 481, 925, 1247, 1681, 1729, 1825, 2059, 2275, 2653, 2821, 3053, 3790, 4745, 4927, 5461, 6175, 6305, 6505, 6601, 7201, 8365, 8911, 9031, 9475, 9730, 9850, 10585, 11041, 12025, 12209, 12403, 13366, 13427, 13747

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OFFSET

1,1

COMMENTS

Composite numbers n such that 51^(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 = 51; 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 *)

Select[Range[15000], CompositeQ[#]&&PowerMod[51, #-1, #]==1&] (* Harvey P. Dale, Oct 20 2016 *)

CROSSREFS

Cf. A001567 (pseudoprimes to base 2).

Sequence in context: A163631 A100536 A024838 * A022670 A072277 A283243

Adjacent sequences: A020176 A020177 A020178 * A020180 A020181 A020182

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved