A003564 Least number m such that 8^m == +- 1 (mod 8n + 1).

1, 4, 10, 5, 10, 7, 3, 2, 3, 9, 11, 8, 4, 14, 55, 7, 34, 14, 8, 11, 26, 29, 6, 16, 11, 15, 5, 20, 29, 4, 41, 8, 26, 4, 35, 68, 15, 10, 26, 53, 23, 7, 44, 44, 57, 20, 14, 20, 65, 100, 34, 23, 40, 12, 14, 112, 38, 20, 35, 6, 27, 35, 50, 3, 130, 253, 89, 6, 13, 40

Offset

1,2

Links

Table of n, a(n) for n=1..70.

Mathematica

lnm[n_]:=Module[{m=1}, While[PowerMod[8, m, 8n+1]!=1&&PowerMod[ 8, m, 8n+1] !=8n, m++]; m]; Array[lnm, 60] (* Harvey P. Dale, Jul 17 2016 *)

Crossrefs

Sequence in context: A336988 A200454 A303052 * A347116 A205016 A241619

Adjacent sequences: A003561 A003562 A003563 * A003565 A003566 A003567

Keyword

nonn

Author

N. J. A. Sloane

Status

approved