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 A372789 #10 Jul 19 2024 13:29:37
%S A372789 3,6,4,9,6,8,6,12,5,12,6,12,6,12,8,15,6,10,6,18,8,12,6,16,9,12,6,18,6,
%T A372789 16,6,18,8,12,12,15,6,12,8,24,6,16,6,18,10,12,6,20,9,18,8,18,6,12,12,
%U A372789 24,8,12,6,24,6,12,10,21,12,16,6,18,8,24,6,20,6,12,12
%N A372789 Number of divisors of 9n; a(n) = tau(9*n) = A000005(9*n).
%H A372789 Antti Karttunen, <a href="/A372789/b372789.txt">Table of n, a(n) for n = 1..65537</a>
%H A372789 Vaclav Kotesovec, <a href="/A372789/a372789.jpg">Graph - the asymptotic ratio (100000 terms)</a>
%F A372789 Sum_{k=1..n} a(k) ~ (21*n*(log(n) + 2*gamma - 1) + n*6*log(3)) / 9, where gamma is the Euler-Mascheroni constant A001620.
%t A372789 Table[DivisorSigma[0, 9*n], {n, 1, 150}]
%o A372789 (PARI) A372789(n) = numdiv(9*n); \\ _Antti Karttunen_, Jul 19 2024
%Y A372789 Cf. A283123.
%Y A372789 Cf. A000005, A099777, A372713, A372784, A372785, A372786, A372787, A372788, A372790, A372791, A372792.
%K A372789 nonn
%O A372789 1,1
%A A372789 _Vaclav Kotesovec_, May 13 2024