A020176 - OEIS

A020176

Pseudoprimes to base 48.

49, 91, 245, 259, 329, 427, 481, 637, 703, 793, 833, 1105, 1267, 1645, 1729, 1813, 1891, 1921, 2257, 2303, 2305, 2353, 2465, 2701, 2821, 2989, 3367, 3439, 4465, 4753, 5185, 5537, 5551, 5611, 5951, 6533, 6601, 6697, 6721, 7345, 8869, 8911, 9457, 9881, 10021

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OFFSET

1,1

COMMENTS

Composite numbers n such that 48^(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 = 48; 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[11000], CompositeQ[#]&&PowerMod[48, #-1, #]==1&] (* Harvey P. Dale, Feb 26 2022 *)

CROSSREFS