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A262105
Pseudoprimes to base 8, written in base 8.
7
11, 25, 55, 77, 101, 151, 165, 205, 231, 347, 421, 525, 741, 777, 1061, 1111, 1205, 1213, 1535, 1665, 1751, 2121, 2401, 2525, 2553, 2611, 3005, 3161, 3175, 3301, 3371, 3561, 3777, 4171, 4641, 4705, 5215, 5405, 6111, 6143
OFFSET
1,1
LINKS
FORMULA
a(n) = A007094(A020137(n)).
MATHEMATICA
base = 8; t = {}; n = 1;
While[Length[t] < 40, n++;
If[! PrimeQ[n] && PowerMod[base, n - 1, n] == 1, AppendTo[t, FromDigits@ IntegerDigits[n, 8]]]]; t
CROSSREFS
Cf. A007094 (Numbers in base 8), A020137 (Pseudoprimes to base 8).
Sequence in context: A161532 A328560 A118648 * A105270 A039337 A043160
KEYWORD
nonn,base
AUTHOR
Abdul Gaffar Khan, Sep 11 2015
STATUS
approved