A035861 Coordination sequence for A_35 lattice.

1, 1260, 397530, 56007420, 4473493290, 231169970556, 8410030153770, 228497569705260, 4843702165221990, 82862496597685980, 1175204732233352562, 14124686337489935340, 146512211150601025170

Offset

0,2

Links

Table of n, a(n) for n=0..12.

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.

Index entries for linear recurrences with constant coefficients, signature (35, -595, 6545, -52360, 324632, -1623160, 6724520, -23535820, 70607460, -183579396, 417225900, -834451800, 1476337800, -2319959400, 3247943160, -4059928950, 4537567650, -4537567650, 4059928950, -3247943160, 2319959400, -1476337800, 834451800, -417225900, 183579396, -70607460, 23535820, -6724520, 1623160, -324632, 52360, -6545, 595, -35, 1).

Formula

Sum_{d=1..35} C(36, d)*C(m/2-1, d-1)*C(35-d+m/2, m/2), where norm m is always even.

Crossrefs

Sequence in context: A179725 A101469 A094208 * A230467 A038651 A268126

Adjacent sequences: A035858 A035859 A035860 * A035862 A035863 A035864

Keyword

nonn,easy

Author

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

Status

approved