A035765 Coordination sequence for C_28 lattice.

1, 1568, 410816, 43381856, 2485013888, 90102925472, 2275791199808, 42760427177696, 627099015232256, 7446658555097888, 73704171158808512, 622408788864127328, 4571394778282027136, 29672618403243206048, 172523643553950122304, 908874759952534074336, 4381165944112803116544

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))^28.

Crossrefs

Sequence in context: A099542 A232672 A232036 * A107561 A260144 A221105

Adjacent sequences: A035762 A035763 A035764 * A035766 A035767 A035768

Keyword

nonn,easy

Author

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

Extensions

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

Status

approved