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 A020215 Pseudoprimes to base 87. 1
 86, 91, 133, 217, 247, 301, 385, 403, 473, 559, 589, 817, 1045, 1105, 1111, 1333, 1661, 1705, 1729, 2047, 2365, 2626, 2651, 2821, 3553, 3565, 3785, 3913, 4123, 4141, 4681, 5005, 5461, 5719, 6533, 6601, 7471, 7483, 7657, 8029, 8041, 8401, 8686, 8911, 9331 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Composite numbers n such that 87^(n-1) == 1 (mod n). LINKS T. D. Noe, Table of n, a(n) for n = 1..1000 MATHEMATICA base = 87; 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: A259084 A058907 A045101 * A094776 A095595 A095581 Adjacent sequences:  A020212 A020213 A020214 * A020216 A020217 A020218 KEYWORD nonn AUTHOR STATUS approved

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Last modified December 7 03:00 EST 2019. Contains 329836 sequences. (Running on oeis4.)