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 A284326 #29 May 17 2023 04:15:13
%S A284326 1,3,4,7,6,6,8,15,13,18,12,10,14,24,24,31,18,15,20,42,32,36,24,18,31,
%T A284326 42,40,56,30,36,32,63,48,54,48,19,38,60,56,90,42,48,44,84,78,72,48,34,
%U A284326 57,93,72,98,54,42,72,120,80,90,60,60,62,96,104,127,84,72,68
%N A284326 Sum of the divisors of n that are not divisible by 6.
%H A284326 Seiichi Manyama, <a href="/A284326/b284326.txt">Table of n, a(n) for n = 1..10000</a>
%F A284326 G.f.: Sum_{k>=1} k*x^k/(1 - x^k) - 6*k*x^(6*k)/(1 - x^(6*k)). - _Ilya Gutkovskiy_, Mar 25 2017
%F A284326 Sum_{k=1..n} a(k) ~ (5*Pi^2/72) * n^2. - _Amiram Eldar_, Oct 04 2022
%F A284326 Dirichlet g.f. (1-6^(1-s))*zeta(s-1)*zeta(s), but not multiplicative. - _R. J. Mathar_, May 17 2023
%t A284326 Table[Sum[Boole[Mod[d,6]>0] d , {d, Divisors[n]}], {n,100}] (* _Indranil Ghosh_, Mar 25 2017 *)
%t A284326 Table[Total[Select[Divisors[n],Mod[#,6]!=0&]],{n,100}] (* _Harvey P. Dale_, Feb 25 2020 *)
%o A284326 (PARI) for(n=1, 100, print1(sumdiv(n, d, ((d%6)>0)*d),", ")) \\ _Indranil Ghosh_, Mar 25 2017
%o A284326 (Python)
%o A284326 from sympy import divisors
%o A284326 print([sum([i for i in divisors(n) if i%6]) for n in range(1, 101)]) # _Indranil Ghosh_, Mar 25 2017
%Y A284326 Cf. Sum of the divisors of n that are not divisible by k: A046913 (k=3), A046897 (k=4), A116073 (k=5), this sequence (k=6), A113957 (k=7), A284341 (k=8), A116607 (k=9), A284344 (k=10).
%K A284326 nonn
%O A284326 1,2
%A A284326 _Seiichi Manyama_, Mar 25 2017