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 A386746 #14 Aug 03 2025 10:07:27
%S A386746 0,1,40,270,1344,3250,10800,17150,43520,66339,130000,162382,362880,
%T A386746 373490,686000,877500,1396736,1424770,2653560,2482958,4368000,4630500,
%U A386746 6495280,6448510,11750400,10171875,14939600,16140060,23049600,20535538,35100000,28658942,44728320
%N A386746 a(n) = n^3*sigma_2(n).
%H A386746 Vincenzo Librandi, <a href="/A386746/b386746.txt">Table of n, a(n) for n = 0..9000</a>
%F A386746 G.f.: Sum_{k>=1} k^5*x^k*(x^(2*k) + 4*x^k + 1)/(1 - x^k)^4. - _Amiram Eldar_, Aug 01 2025
%F A386746 a(n) = n^3*A001157(n).
%F A386746 Dirichlet g.f.: zeta(s-3)*zeta(s-5). - _R. J. Mathar_, Aug 03 2025
%t A386746 Table[n^3*DivisorSigma[2, n], {n, 0, 40}]
%t A386746 nmax = 40; CoefficientList[Series[Sum[k^5*x^k*(x^(2*k) + 4*x^k + 1)/(1 - x^k)^4, {k, 1, nmax}], {x, 0, nmax}], x]
%o A386746 (Magma) [0] cat [n^3*DivisorSigma(2, n): n in [1..35]]; // _Vincenzo Librandi_, Aug 02 2025
%Y A386746 Cf. A001157, A328259, A386745.
%K A386746 nonn,mult
%O A386746 0,3
%A A386746 _Vaclav Kotesovec_, Aug 01 2025