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 A091258 #33 Aug 28 2024 01:04:42
%S A091258 1,1,1,7,1,1,1,1,13,1,1,1,1,1,1,1,1,13,1,1,1,1,1,1,31,1,1,7,1,1,1,7,1,
%T A091258 1,1,91,1,1,1,1,1,1,1,7,13,1,1,1,19,31,1,7,1,1,1,1,1,1,1,1,1,1,13,1,1,
%U A091258 1,1,1,1,1,1,1,1,1,31,1,1,1,1,1,1,1,1,1,1,1,1,1,1,13,1,7,1,1,1,1,1,19,13
%N A091258 Denominator of sigma_3(n)/sigma(n).
%C A091258 Conjecture: The set of distinct terms is A004611. - _Michel Marcus_, Aug 10 2024
%H A091258 Antti Karttunen, <a href="/A091258/b091258.txt">Table of n, a(n) for n = 1..65537</a>
%t A091258 Denominator[Table[DivisorSigma[3,n]/DivisorSigma[1,n],{n,100}]] (* _Harvey P. Dale_, Oct 06 2017 *)
%o A091258 (PARI) a(n) = denominator(sigma(n, 3)/sigma(n)); \\ _Michel Marcus_, Dec 29 2013
%Y A091258 Cf. A001158, A000203, A091259 (numerators), A091260.
%Y A091258 Cf. A002476, A004611.
%K A091258 easy,nonn,frac
%O A091258 1,4
%A A091258 _Labos Elemer_, Feb 12 2004