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 A385230 #21 Jun 30 2025 04:38:06 %S A385230 1,3,7,9,5,13,15,25,9,7,17,37,13,43,45,49,19,67,23,73,39,79,87,93,97, %T A385230 11,51,105,19,115,127,65,135,139,71,37,153,163,165,169,175,177,61,189, %U A385230 95,193,199,101,205,207,213,107,219,235,17,83,23,85,265,89,91,277,279,141,59,75 %N A385230 Odd multiplicative orders of -4 modulo primes. %C A385230 Odd elements in A380531. %C A385230 a(n) is the multiplicative order of -4 modulo A385224(n). %H A385230 Jianing Song, <a href="/A385230/b385230.txt">Table of n, a(n) for n = 1..10000</a> %t A385230 Select[Map[MultiplicativeOrder[-4, #] &, Prime[Range[200]]], OddQ] (* _Paolo Xausa_, Jun 30 2025 *) %o A385230 (PARI) forprime(p=3, 1e4, z=znorder(Mod(-4, p)); if(z%2, print1(z, ", "))) %Y A385230 Cf. A380531, A385224 (corresponding primes). %Y A385230 Cf. other bases: A139686 (base 2), A385226 (base 3), A385227 (base 4), A385193 (base 5), A385228 (base -2), A385229 (base -3), this sequence (base -4), A385231 (base -5). %K A385230 nonn,easy %O A385230 1,2 %A A385230 _Jianing Song_, Jun 22 2025