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 A015667 #11 Oct 23 2018 07:19:13
%S A015667 1,7,35,105,273,4095,38115,86625,540225,22444695,215417475,1819488825,
%T A015667 18942548625,273922023375,9015078147075,69890980784625,
%U A015667 -152873391045375,34948775541054375,718624343013451875,6694758964203935625
%N A015667 Expansion of e.g.f. theta_3^(7/2).
%D A015667 J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 102.
%H A015667 Seiichi Manyama, <a href="/A015667/b015667.txt">Table of n, a(n) for n = 0..448</a>
%t A015667 nmax = 25; CoefficientList[Series[EllipticTheta[3, 0, x]^(7/2), {x, 0, nmax}], x] * Range[0, nmax]! (* _Vaclav Kotesovec_, Oct 23 2018 *)
%K A015667 sign
%O A015667 0,2
%A A015667 _N. J. A. Sloane_