A020290 - OEIS

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A020290

Strong pseudoprimes to base 64.

9, 21, 63, 65, 133, 231, 341, 481, 511, 651, 1387, 1417, 1541, 1661, 2047, 2501, 3171, 3277, 3641, 4033, 4097, 4371, 4681, 5461, 5963, 6533, 6951, 7107, 7161, 8321, 8911, 9709, 10261, 11041, 13333, 13747, 14491, 14981, 15709, 15841, 16589, 19561, 19951

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..300

Index entries for sequences related to pseudoprimes

MATHEMATICA

strongPseudoprimeQ[b_, n_] := Module[{rems = Table[PowerMod[b, (n - 1)/2^expo, n], {expo, 0, IntegerExponent[n - 1, 2]}]}, (rems[[-1]] == 1 || MemberQ[rems, n - 1]) && PowerMod[b, n - 1, n] == 1]; max = 5000; Select[Complement[Range[2, max], Prime[Range[PrimePi[max]]]], strongPseudoprimeQ[64, #] &] (* Alonso del Arte, Aug 08 2018 *)

CROSSREFS

Sequence in context: A320896 A127989 A147337 * A020288 A338007 A147466

Adjacent sequences: A020287 A020288 A020289 * A020291 A020292 A020293

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved