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A020290 Strong pseudoprimes to base 64. 1
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
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
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified April 24 16:34 EDT 2024. Contains 371961 sequences. (Running on oeis4.)