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 A345657 #21 Sep 24 2023 10:19:05
%S A345657 1,0,0,0,196848,24576,17356032,6782976,448438518,274735104,5823343872,
%T A345657 4366565376,48362165472,39912726528,292010062848,253343072256,
%U A345657 1393763244336,1241347399680,5550621292032,5010361122816
%N A345657 Theta series of the canonical laminated lattice LAMBDA_26.
%C A345657 Theta series is an element of the space of modular forms on Gamma_1(24) with Kronecker character -3 in modulus 24, weight 13, and dimension 52 over the integers.
%D A345657 J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 178.
%H A345657 J. H. Conway and N. J. A. Sloane, <a href="https://doi.org/10.2307/2007025">Laminated lattices</a>, Annals of Math., 116 (1982), pp. 593-620. A revised version appears as Chapter 6 of "Sphere Packings, Lattices and Groups" by J. H. Conway and N. J. A. Sloane, Springer-Verlag, NY, 1988.
%H A345657 J. H. Conway and N. J. A. Sloane, <a href="/A005135/a005135.png">The "shower" showing containments among the laminated lattices up to dimension 48</a> (Fig 3 from the Annals paper, also Fig. 6.1 in the Sphere packing book).
%H A345657 G. Nebe and N. J. A. Sloane, <a href="https://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/LAMBDA26.html">Home page for this lattice</a>
%H A345657 <a href="/index/La#laminated">Index entries for sequences related to laminated lattices</a>
%e A345657 1 + 196848*q^8 + 24576*q^10 + ...
%o A345657 (Magma)
%o A345657 L := Lattice("Lambda", 26);
%o A345657 T<q> := ThetaSeries(L,14);
%o A345657 C := Coefficients(T);
%o A345657 [C[2*i-1] : i in [1..8]];
%Y A345657 Cf. A005135, A023942, A008408.
%K A345657 nonn,more
%O A345657 0,5
%A A345657 _Andy Huchala_, Jun 21 2021
%E A345657 a(17)-a(19) from _Robin Visser_, Sep 24 2023