A035780 Coordination sequence for C_43 lattice.

1, 3698, 2281666, 564939762, 75337937666, 6297987950322, 362379485902530, 15295775774728050, 496112377224088578, 12810603157435946354, 270825129557394211522, 4795024968771774597362, 72448989645639523846914

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))^43.

Maple

seq(coeff(series(((1+x)/(1-x))^43, x, n+1), x, n), n=0..30, 2); # Muniru A Asiru, Aug 12 2018

Crossrefs

Cf. A035738.

Sequence in context: A188155 A061660 A219067 * A108004 A176386 A204525

Adjacent sequences: A035777 A035778 A035779 * A035781 A035782 A035783

Keyword

nonn,easy

Author

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

Extensions

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

Status

approved