A035779 Coordination sequence for C_42 lattice.

1, 3528, 2076816, 490681688, 62456027424, 4985149915368, 273998113272240, 11053262513080440, 342841481215636032, 8471578904288191496, 171504713146698879696, 2910051399340259388312, 42170689218812731525984

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))^42.

Maple

seq(coeff(series(((1+x)/(1-x))^42, x, n+1), x, n), n=0..30, 2); # Muniru A Asiru, Aug 12 2018

Crossrefs

Cf. A035737.

Sequence in context: A064256 A232555 A330841 * A108003 A176139 A354542

Adjacent sequences: A035776 A035777 A035778 * A035780 A035781 A035782

Keyword

nonn,easy

Author

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

Extensions

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

Status

approved