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A020231 Strong pseudoprimes to base 5. 10
781, 1541, 5461, 5611, 7813, 13021, 14981, 15751, 24211, 25351, 29539, 38081, 40501, 44801, 53971, 79381, 100651, 102311, 104721, 112141, 121463, 133141, 141361, 146611, 195313, 211951, 216457, 222301, 251521, 289081, 290629, 298271, 315121 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..715

Index entries for sequences related to pseudoprimes

Eric Weisstein's World of Mathematics, Strong Pseudoprime

MATHEMATICA

nmax = 400000; sppQ[n_?EvenQ, _] := False; sppQ[n_?PrimeQ, _] := False; sppQ[n_, b_] := (s = IntegerExponent[n-1, 2]; d = (n-1)/2^s; If[ PowerMod[b, d, n] == 1, Return[True], Do[If[PowerMod[b, d*2^r, n] == n-1, Return[True]], {r, 0, s - 1}]]); A020231 = {}; n = 1; While[n < nmax, n = n+2; If[sppQ[n, 5] == True, Print[n]; AppendTo[A020231, n]]]; A020231 (* Jean-Fran├žois Alcover, Oct 20 2011, after R. J. Mathar *)

CROSSREFS

Sequence in context: A250952 A139400 A115467 * A141390 A038477 A236888

Adjacent sequences:  A020228 A020229 A020230 * A020232 A020233 A020234

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified May 25 01:23 EDT 2016. Contains 273256 sequences.