

A020231


Strong pseudoprimes to base 5.


9



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
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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[n1, 2]; d = (n1)/2^s; If[ PowerMod[b, d, n] == 1, Return[True], Do[If[PowerMod[b, d*2^r, n] == n1, 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 (* JeanFrançois 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



