A380533 a(n) is the multiplicative order of -6 modulo prime(n); a(1) = a(2) = 0 for completion.

0, 0, 2, 1, 5, 12, 16, 18, 22, 7, 3, 4, 40, 6, 46, 13, 29, 60, 66, 70, 36, 39, 41, 88, 12, 5, 51, 53, 108, 112, 63, 65, 136, 46, 74, 75, 156, 54, 166, 86, 89, 60, 38, 96, 7, 99, 210, 111, 113, 228, 232, 34, 20, 125, 256, 262, 67, 135, 276, 56

Offset

1,3

Links

Jianing Song, Table of n, a(n) for n = 1..10000

Mathematica

A380533[n_] := If[n < 3, 0, MultiplicativeOrder[-6, Prime[n]]];
Array[A380533, 100] (* Paolo Xausa, Jun 29 2025 *)

Prog

(PARI) a(n, {k=-6}) = my(p = prime(n)); if(k%p==0, 0, znorder(Mod(k, p)))

Crossrefs

Cf. A105878 (primes having primitive root -6).

Cf. bases 2..10: A014664, A062117, A082654, A211241, A211242, A211243, A211244, A211245, A002371.

Cf. bases -2..-10: A337878 (if first term 1), A380482, A380531, A380532, this sequence, A380540, A380541, A380542, A385222.

Sequence in context: A049950 A095216 A307258 * A174317 A394845 A144237

Adjacent sequences: A380530 A380531 A380532 * A380534 A380535 A380536

Keyword

nonn,easy

Author

Jianing Song, Jun 27 2025

Status

approved