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A020170 Pseudoprimes to base 42. 1
205, 451, 529, 559, 697, 1105, 1247, 1441, 1541, 1763, 1765, 1807, 1891, 1921, 1991, 2465, 2665, 5371, 5611, 5977, 6001, 7345, 7421, 8041, 8749, 9773, 10585, 10621, 11041, 12167, 12403, 13333, 13981, 14473, 14491, 14981, 15457, 17611, 18721, 22399 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Composite numbers n such that 42^(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 = 42; 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: A191834 A042983 A186475 * A260471 A249703 A015974

Adjacent sequences:  A020167 A020168 A020169 * A020171 A020172 A020173

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified June 6 04:04 EDT 2020. Contains 334858 sequences. (Running on oeis4.)