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A020144 Pseudoprimes to base 16. 1
15, 51, 85, 91, 255, 341, 435, 451, 561, 595, 645, 703, 1105, 1247, 1261, 1271, 1285, 1387, 1581, 1687, 1695, 1729, 1891, 1905, 2047, 2071, 2091, 2431, 2465, 2701, 2821, 3133, 3277, 3367, 3655, 3683, 4033, 4369, 4371, 4681, 4795, 4859, 5083, 5151, 5461 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Composite numbers n such that 16^(n-1) == 1 (mod n). [From Michel Lagneau, Feb 18 2012]

LINKS

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

Index entries for sequences related to pseudoprimes

MATHEMATICA

base = 16; 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: A227129 A238574 A238575 * A235040 A075933 A075929

Adjacent sequences:  A020141 A020142 A020143 * A020145 A020146 A020147

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified September 26 01:25 EDT 2017. Contains 292500 sequences.