A035782 Coordination sequence for C_45 lattice.

1, 4050, 2736450, 741759570, 108242937090, 9895463694162, 622155720985410, 28667877399006930, 1013960660749554690, 28517022732422789330, 655766098851343900482, 12611613545459896364370, 206678785994044883684610

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))^45.

Maple

seq(coeff(series(((1+x)/(1-x))^45, x, n+1), x, n), n=0..30, 2); # Muniru A Asiru, Aug 12 2018

Crossrefs

Cf. A035740.

Sequence in context: A001382 A090058 A251032 * A108006 A320207 A320216

Adjacent sequences: A035779 A035780 A035781 * A035783 A035784 A035785

Keyword

nonn,easy

Author

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

Extensions

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

Status

approved