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 A020175 Pseudoprimes to base 47. 1
 46, 65, 69, 85, 221, 259, 341, 345, 427, 481, 506, 561, 645, 703, 721, 793, 805, 874, 897, 946, 1105, 1173, 1426, 1581, 1649, 1702, 1729, 1771, 1891, 2257, 2465, 2737, 2806, 2821, 3145, 3201, 3811, 4301, 4485, 5185, 5461, 5865, 6283, 6305, 6601, 6943, 8911 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Composite numbers n such that 47^(n-1) == 1 (mod n). LINKS R. J. Mathar, Table of n, a(n) for n=1..1163 Index entries for sequences related to pseudoprimes MATHEMATICA base = 47; 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 *) Select[Range[9000], CompositeQ[#]&&PowerMod[47, #-1, #]==1&] (* Harvey P. Dale, Sep 27 2023 *) CROSSREFS Cf. A001567 (pseudoprimes to base 2). Sequence in context: A039424 A043247 A044027 * A118698 A350203 A103381 Adjacent sequences: A020172 A020173 A020174 * A020176 A020177 A020178 KEYWORD nonn AUTHOR David W. Wilson STATUS approved

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Last modified June 13 17:32 EDT 2024. Contains 373391 sequences. (Running on oeis4.)