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A020160 Pseudoprimes to base 32. 3
25, 33, 93, 165, 205, 217, 325, 341, 385, 425, 465, 561, 645, 697, 793, 825, 1023, 1025, 1045, 1057, 1065, 1105, 1353, 1387, 1525, 1705, 1729, 1905, 2047, 2317, 2325, 2465, 2665, 2701, 2761, 2821, 3053, 3157, 3277, 3565, 3813, 4033, 4123, 4141, 4369, 4371 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Composite numbers n such that 32^(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

pseudos32 = {}; n = 1; While[Length[pseudos32] < 100, n++; If[!PrimeQ[n] && PowerMod[32, n - 1, n] == 1, AppendTo[pseudos32, n]]]; pseudos32 (* T. D. Noe, Feb 21 2012 *)

max = 5000; Complement[Select[Range[max], PowerMod[32, # - 1, #] == 1 &], Prime[Range[PrimePi[max]]]] (* Alonso del Arte, Jun 12 2018 *)

PROG

(MAGMA) [n: n in [3..10000 by 2] | IsOne(Modexp(32, n-1, n)) and not IsPrime(n)]; // Vincenzo Librandi, Jun 13 2018

CROSSREFS

Cf. A001567 (pseudoprimes to base 2).

Sequence in context: A129074 A188443 A068411 * A075452 A231572 A020258

Adjacent sequences:  A020157 A020158 A020159 * A020161 A020162 A020163

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified March 29 05:39 EDT 2020. Contains 333105 sequences. (Running on oeis4.)