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 A053452 #21 Feb 19 2019 01:24:51
%S A053452 1,1,1,2,3,1,2,5,3,3,2,8,9,2,5,11,10,3,3,14,15,4,8,6,9,9,2,4,21,5,11,
%T A053452 23,21,10,3,26,10,3,14,29,5,15,8,6,11,8,6,35,6,9,9,15,39,2,4,41,8,21,
%U A053452 5,44,3,11,23,18,24,21,10,50,17,3,26,53,27,10,6,56,22,14,29,24,5,5,15,50
%N A053452 Multiplicative order of 9 mod n, where gcd(n, 9) = 1.
%C A053452 Essentially the same as A050981. [_R. J. Mathar_, Oct 13 2008]
%H A053452 Muniru A Asiru, <a href="/A053452/b053452.txt">Table of n, a(n) for n = 1..10000</a>
%t A053452 MultiplicativeOrder[9, #] & /@ Select[ Range@ 125, GCD[9, #] == 1 &] (* _Robert G. Wilson v_, Apr 05 2011 *)
%o A053452 (PARI) lista(nn) = {for(n=1, nn, if (gcd(n, 9) == 1, print1(znorder(Mod(9, n)), ", ")););} \\ _Michel Marcus_, Feb 09 2015
%o A053452 (GAP) List(Filtered([1..210],n->Gcd(n,9)=1),n->OrderMod(9,n)); # _Muniru A Asiru_, Feb 17 2019
%Y A053452 Cf. A050981, A070679.
%K A053452 nonn
%O A053452 1,4
%A A053452 _David W. Wilson_