A035787 Coordination sequence for C_50 lattice.

1, 5000, 4170000, 1394447000, 250799764000, 28222682700200, 2180706863326000, 123252789641763000, 5335428332027176000, 183203070393610797000, 5129723834328569406800, 119780004243882975543000, 2376073555319729124284000, 40672867087351099089831400

Offset: 0

Author

Joan Serra-Sagrista (jserra(AT)ccd.uab.es)

Keywords

• nonn
• easy

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..10000
• R. Bacher, P. de la Harpe and B. Venkov, Séries de croissance et séries d'Ehrhart associées aux réseaux de racines, C. R. Acad. Sci. Paris, 325 (Series 1) (1997), 1137-1142.
• J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (pdf).
• Joan Serra-Sagrista, Enumeration of lattice points in l_1 norm, Inf. Proc. Lett. 76 (1-2) (2000) 39-44.

Crossrefs

Cf. A035745.

Formula

a(n) = [x^(2n)] ((1+x)/(1-x))^50.

Extensions

Recomputed by N. J. A. Sloane, Nov 25 1998