A262105 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

A262105

Pseudoprimes to base 8, written in base 8.

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

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).

Cf. A258189, A262101, A262102, A262103, A262104, A262154.

Sequence in context: A161532 A328560 A118648 * A105270 A039337 A043160

Adjacent sequences: A262102 A262103 A262104 * A262106 A262107 A262108

KEYWORD

nonn,base

AUTHOR

Abdul Gaffar Khan, Sep 11 2015

STATUS

approved