A020182 Pseudoprimes to base 54.

55, 265, 341, 361, 385, 583, 781, 1045, 1105, 1247, 1729, 1855, 2201, 2465, 2701, 2821, 2863, 2915, 3445, 4033, 4069, 4081, 5005, 5317, 5461, 6095, 6601, 7471, 7957, 8321, 8911, 9073, 10585, 11713, 13357, 14585, 14701, 14905, 15409, 15841, 17755, 18721

Offset

1,1

Comments

Composite numbers n such that 54^(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

Mathematica

base = 54; 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[20000], !PrimeQ[#]&&PowerMod[54, #-1, #]==1&] (* Harvey P. Dale, Jul 03 2019 *)

Crossrefs

Cf. A001567 (pseudoprimes to base 2).

Sequence in context: A158658 A296036 A286854 * A159746 A212408 A350286

Adjacent sequences: A020179 A020180 A020181 * A020183 A020184 A020185

Keyword

nonn

Author

David W. Wilson

Status

approved