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A020205 Pseudoprimes to base 77. 1
4, 38, 39, 57, 65, 76, 247, 285, 703, 741, 969, 1105, 1387, 1513, 1653, 1891, 2465, 2701, 2806, 2965, 3705, 4033, 4371, 4636, 5073, 5461, 5713, 5785, 6305, 6441, 6533, 6541, 7633, 7709, 7957, 10081, 10585, 10777, 11229, 12871, 13051, 16017, 16745, 17081 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Composite numbers n such that 77^(n-1) == 1 (mod n).

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

Index entries for sequences related to pseudoprimes

MATHEMATICA

base = 77; 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: A073237 A218334 A121672 * A265437 A003633 A129310

Adjacent sequences:  A020202 A020203 A020204 * A020206 A020207 A020208

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified May 28 17:37 EDT 2020. Contains 334684 sequences. (Running on oeis4.)