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 A385227 #16 Jun 28 2025 16:03:50 %S A385227 1,3,5,9,11,5,7,23,29,33,35,9,39,41,11,51,53,7,65,69,15,81,83,89,95, %T A385227 99,105,37,113,29,119,25,131,135,35,47,51,155,15,21,173,179,183,189, %U A385227 191,209,43,73,221,231,233,239,243,245,83,251,261,273,281,57,293 %N A385227 Odd multiplicative orders of 4 modulo primes. %C A385227 a(n) is the multiplicative order of 4 modulo A385221(n). %C A385227 Odd elements in A082654. %H A385227 Jianing Song, <a href="/A385227/b385227.txt">Table of n, a(n) for n = 1..10000</a> %t A385227 Select[Map[MultiplicativeOrder[4, #] &, Prime[Range[200]]], OddQ] (* _Paolo Xausa_, Jun 28 2025 *) %o A385227 (PARI) forprime(p=3, 1e4, z=znorder(Mod(4, p)); if(z%2, print1(z, ", "))) %Y A385227 Cf. A082654, A385221 (corresponding primes). %Y A385227 Cf. other bases: A139686 (base 2), A385226 (base 3), this sequence (base 4), A385193 (base 5), A385228 (base -2), A385229 (base -3), A385230 (base -4), A385231 (base -5). %K A385227 nonn,easy %O A385227 1,2 %A A385227 _Jianing Song_, Jun 22 2025