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 A386748 #17 Aug 03 2025 10:14:06
%S A386748 0,1,136,2214,17472,78250,301104,823886,2236928,4842747,10642000,
%T A386748 19488502,38683008,62750714,112048496,173245500,286330880,410343586,
%U A386748 658613592,893878598,1367184000,1824083604,2650436272,3404837614,4952558592,6113296875,8534097104,10591107372
%N A386748 a(n) = n^3*sigma_4(n).
%H A386748 Vincenzo Librandi, <a href="/A386748/b386748.txt">Table of n, a(n) for n = 0..8000</a>
%F A386748 G.f.: Sum_{k>=1} k^7*x^k*(x^(2*k) + 4*x^k + 1)/(1 - x^k)^4. - _Amiram Eldar_, Aug 01 2025
%F A386748 a(n) = n^3*A001159(n).
%F A386748 Dirichlet g.f.: zeta(s-3)*zeta(s-7). - _R. J. Mathar_, Aug 03 2025
%t A386748 Table[n^3*DivisorSigma[4, n], {n, 0, 40}]
%t A386748 nmax = 40; CoefficientList[Series[Sum[k^7*x^k*(x^(2*k) + 4*x^k + 1)/(1 - x^k)^4, {k, 1, nmax}], {x, 0, nmax}], x]
%o A386748 (Magma) [0] cat [n^3*DivisorSigma(4, n): n in [1..35]]; // _Vincenzo Librandi_, Aug 02 2025
%Y A386748 Cf. A000578, A001159, A386749, A386747.
%K A386748 nonn,mult
%O A386748 0,3
%A A386748 _Vaclav Kotesovec_, Aug 01 2025