A009661 Smallest number m such that m^m+1 is divisible by n.

0, 0, 5, 3, 2, 5, 3, 7, 17, 9, 21, 11, 6, 3, 29, 15, 24, 17, 27, 19, 41, 21, 11, 23, 18, 25, 53, 3, 14, 29, 15, 31, 35, 33, 69, 35, 6, 27, 77, 39, 25, 41, 63, 35, 89, 11, 23, 47, 97, 49, 101, 51, 26, 53, 109, 55, 113, 35, 117, 59, 30, 15, 125, 63, 18, 35, 99, 67, 11, 69, 35, 71, 9, 27

Offset: 1

Author

David W. Wilson

Keywords

• nonn

Comments

If n is odd, then a(n) <= 2*n - 1. If n is even, then a(n) <= n - 1. - Thomas Ordowski, Dec 03 2023

Crossrefs

Cf. A014566, A133090, A268466.

Programs

PARI

a(n) = my(m=0); while ((1+Mod(m, n)^m) != 0, m++); m; \\ Michel Marcus, Dec 03 2023