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 A035787 #22 Apr 07 2020 08:03:41 %S A035787 1,5000,4170000,1394447000,250799764000,28222682700200, %T A035787 2180706863326000,123252789641763000,5335428332027176000, %U A035787 183203070393610797000,5129723834328569406800,119780004243882975543000,2376073555319729124284000,40672867087351099089831400 %N A035787 Coordination sequence for C_50 lattice. %H A035787 Seiichi Manyama, <a href="/A035787/b035787.txt">Table of n, a(n) for n = 0..10000</a> %H A035787 R. Bacher, P. de la Harpe and B. Venkov, <a href="https://dx.doi.org/10.1016/S0764-4442(97)83542-2">Séries de croissance et séries d'Ehrhart associées aux réseaux de racines</a>, C. R. Acad. Sci. Paris, 325 (Series 1) (1997), 1137-1142. %H A035787 J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (<a href="http://neilsloane.com/doc/Me220.pdf">pdf</a>). %H A035787 Joan Serra-Sagrista, <a href="https://dx.doi.org/10.1016/S0020-0190(00)00119-8">Enumeration of lattice points in l_1 norm</a>, Inf. Proc. Lett. 76 (1-2) (2000) 39-44. %F A035787 a(n) = [x^(2n)] ((1+x)/(1-x))^50. %Y A035787 Cf. A035745. %K A035787 nonn,easy %O A035787 0,2 %A A035787 Joan Serra-Sagrista (jserra(AT)ccd.uab.es) %E A035787 Recomputed by _N. J. A. Sloane_, Nov 25 1998