This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A380482 #32 Jul 07 2025 10:43:41
%S A380482 1,0,4,3,10,6,16,9,22,28,15,9,8,21,46,52,58,5,11,70,12,39,82,88,48,
%T A380482 100,17,106,54,112,63,130,136,69,148,25,39,81,166,172,178,90,190,16,
%U A380482 196,99,105,111,226,114,232,238,120,250,256,262,268,15,138,280
%N A380482 a(n) is the multiplicative order of -3 modulo prime(n); a(2) = 0 for completion.
%H A380482 Jianing Song, <a href="/A380482/b380482.txt">Table of n, a(n) for n = 1..10000</a>
%t A380482 A380482[n_] := If[n == 2, 0, MultiplicativeOrder[-3, Prime[n]]];
%t A380482 Array[A380482, 100] (* _Paolo Xausa_, Jun 29 2025 *)
%o A380482 (PARI) a(n,{k=-3}) = my(p = prime(n)); if(k%p==0, 0, znorder(Mod(k,p)))
%Y A380482 Cf. A105875 (primes having primitive root -3).
%Y A380482 Cf. bases 2..10: A014664, A062117, A082654, A211241, A211242, A211243, A211244, A211245, A002371.
%Y A380482 Cf. bases -2..-10: A337878 (if first term 1), this sequence, A380531, A380532, A380533, A380540, A380541, A380542, A385222.
%K A380482 nonn,easy
%O A380482 1,3
%A A380482 _Jianing Song_, Jun 27 2025