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A020218 Pseudoprimes to base 90. 1
91, 623, 703, 793, 1001, 1157, 1729, 2047, 2413, 2821, 3091, 3367, 4033, 4699, 6281, 6601, 8099, 8321, 8401, 8911, 11521, 11557, 12403, 13021, 13333, 13981, 14701, 14981, 15841, 17701, 19307, 19951, 20017, 20263, 24641, 24661, 25571, 29341, 31021 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Composite numbers n such that 90^(n-1) == 1 (mod n). - Michel Lagneau, Feb 18 2012
LINKS
MATHEMATICA
base = 90; 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: A211447 A188360 A165220 * A217841 A338795 A084319
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified March 28 11:59 EDT 2024. Contains 371246 sequences. (Running on oeis4.)