A016108 Numbers k=3*m+1 such that 2^m == 1 (mod k).

1, 31, 43, 109, 127, 157, 223, 229, 277, 283, 307, 397, 433, 439, 457, 499, 601, 643, 691, 727, 733, 739, 811, 919, 997, 1021, 1051, 1069, 1093, 1327, 1399, 1423, 1459, 1471, 1579, 1597, 1627, 1657, 1699, 1723, 1729, 1753, 1777, 1789, 1801, 1831, 1933, 1999, 2017, 2047, 2089, 2113, 2143, 2179, 2203

Offset

1,2

Comments

Prime terms are listed in A014752.

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

Join[{1}, Select[Table[3m+1, {m, 1000}], PowerMod[2, (#-1)/3, #]==1&]] (* Harvey P. Dale, Apr 26 2016 *)

Crossrefs

Cf. A014752.

Sequence in context: A347035 A364186 A059898 * A014752 A306787 A227622

Adjacent sequences: A016105 A016106 A016107 * A016109 A016110 A016111

Keyword

nonn

Author

Max Alekseyev, Jun 23 2012

Status

approved