A070677 Smallest m in range 1..phi(n) such that 5^m == 1 mod n, or 0 if no such number exists.

0, 1, 2, 1, 0, 2, 6, 2, 6, 0, 5, 2, 4, 6, 0, 4, 16, 6, 9, 0, 6, 5, 22, 2, 0, 4, 18, 6, 14, 0, 3, 8, 10, 16, 0, 6, 36, 9, 4, 0, 20, 6, 42, 5, 0, 22, 46, 4, 42, 0, 16, 4, 52, 18, 0, 6, 18, 14, 29, 0, 30, 3, 6, 16, 0, 10, 22, 16, 22, 0, 5, 6, 72, 36, 0, 9, 30, 4, 39, 0

Offset

1,3

Links

Table of n, a(n) for n=1..80.

Mathematica

Table[SelectFirst[Range[EulerPhi[n]], PowerMod[5, #, n] == 1 &, 0], {n, 80}] (* Paul F. Marrero Romero, Oct 04 2024 *)

Prog

(Magma) [0] cat [Modorder(5, n): n in [2..100]]; // Vincenzo Librandi, Apr 01 2014
(Python)
from sympy import n_order
def A070677(n): return n_order(5, n) if n%5 and n>1 else 0 # Chai Wah Wu, Feb 23 2023

Crossrefs

Cf. A070667-A070675, A002326, A070676, A053447, A070681, A070678, A053451, A070679, A070682, A070680, A070683.

Sequence in context: A355609 A266994 A267072 * A269339 A300192 A366554

Adjacent sequences: A070674 A070675 A070676 * A070678 A070679 A070680

Keyword

nonn

Author

N. J. A. Sloane and Amarnath Murthy, May 08 2002

Status

approved