A035781 Coordination sequence for C_44 lattice.

1, 3872, 2501312, 648339296, 90488748416, 7914446636448, 476256430985280, 21013302552438240, 712041389847515904, 19196735036095030304, 423435066223344657856, 7816588576688121767008, 123043979986038246517888

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))^44.

Maple

seq(coeff(series(((1+x)/(1-x))^44, x, n+1), x, n), n=0..30, 2); # Muniru A Asiru, Aug 12 2018

Crossrefs

Cf. A035739.

Sequence in context: A249325 A249218 A264206 * A108005 A065696 A246735

Adjacent sequences: A035778 A035779 A035780 * A035782 A035783 A035784

Keyword

nonn,easy

Author

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

Extensions

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

Status

approved