A035759 Coordination sequence for C_22 lattice.

1, 968, 156816, 10286936, 368804128, 8453107432, 136585481648, 1663935545976, 16051394232896, 127269237312008, 853941394691792, 4962895187697048, 25459406230618976, 117088340731041064, 489035476964671472, 1875154363323009208, 6661774086773638272, 22100369343864328264

Offset

0,2

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.

Formula

a(n) = [x^(2n)] ((1+x)/(1-x))^22.

Crossrefs

Sequence in context: A142378 A035887 A255656 * A107555 A175991 A030251

Adjacent sequences: A035756 A035757 A035758 * A035760 A035761 A035762

Keyword

nonn,easy

Author

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

Extensions

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

Status

approved