

A020185


Pseudoprimes to base 57.


1



4, 8, 14, 25, 28, 56, 65, 125, 145, 203, 217, 325, 377, 451, 721, 725, 781, 1001, 1105, 1625, 1885, 1891, 2047, 2296, 2465, 2701, 2821, 2911, 3193, 3277, 3565, 3625, 3976, 4141, 4187, 5365, 5425, 6461, 6533, 6601, 7501, 7613, 8029, 8401, 9373, 9425, 10325
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OFFSET

1,1


COMMENTS

Composite numbers n such that 57^(n1) == 1 (mod n).


LINKS



MATHEMATICA

base = 57; t = {}; n = 1; While[Length[t] < 100, n++; If[! PrimeQ[n] && PowerMod[base, n1, n] == 1, AppendTo[t, n]]]; t (* T. D. Noe, Feb 21 2012 *)


PROG

(PARI) isA020185(n) = (Mod(57, n)^(n1)==1) && (!isprime(n))


CROSSREFS

Cf. A001567 (pseudoprimes to base 2).


KEYWORD

nonn


AUTHOR



STATUS

approved



