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 A386778 #14 Aug 04 2025 07:11:17
%S A386778 0,1,1028,59058,1052688,9765650,60711624,282475298,1077952576,
%T A386778 3487315923,10039088200,25937424722,62169647904,137858492018,
%U A386778 290384606344,576739757700,1103823438080,2015993900738,3584960768844,6131066258162,10280182567200,16682426149284,26663672614216
%N A386778 a(n) = n^2*sigma_8(n).
%H A386778 Vincenzo Librandi, <a href="/A386778/b386778.txt">Table of n, a(n) for n = 0..10000</a>
%F A386778 G.f.: Sum_{k>=1} k^10*x^k*(1 + x^k)/(1 - x^k)^3.
%F A386778 a(n) = n^2*A013956(n).
%F A386778 Dirichlet g.f.: zeta(s-2)*zeta(s-10). - _R. J. Mathar_, Aug 03 2025
%t A386778 Table[n^2*DivisorSigma[8, n], {n, 0, 30}]
%t A386778 nmax = 30; CoefficientList[Series[Sum[k^10*x^k*(1 + x^k)/(1 - x^k)^3, {k, 1, nmax}], {x, 0, nmax}], x]
%o A386778 (Magma) [0] cat [n^2*DivisorSigma(8, n): n in [1..35]]; // _Vincenzo Librandi_, Aug 04 2025
%Y A386778 Cf. A282097, A386745, A282099, A386747, A282751, A386777, A282753.
%Y A386778 Cf. A013956, A386751.
%K A386778 nonn,mult
%O A386778 0,3
%A A386778 _Vaclav Kotesovec_, Aug 02 2025