A035754 Coordination sequence for C_17 lattice.

1, 578, 56066, 2220098, 48663554, 693230658, 7094825730, 55871829570, 355761664002, 1900906442306, 8769652761346, 35721495233602, 130777539341314, 436553052633154, 1344455730686722, 3857284100508226, 10393582407041026, 26482855453375042, 64180094992435970

Offset

0,2

Links

Seiichi Manyama, Table of n, a(n) for n = 0..10000

R. Bacher, P. de la Harpe and B. Venkov, Series de croissance et series d'Ehrhart associees aux reseaux 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

G.f.: Sum_{n>=0} a(n)x^(2n) = ( ((1+x)/(1-x))^17 +((1-x)/(1+x))^17 )/2. - Michael Somos, Aug 03 2006

Prog

(PARI) {a(n)=if(n<0, 0, n*=2; polcoeff( ((1+x)/(1-x)+x*O(x^n))^17, n))} /* Michael Somos, Aug 03 2006 */

Crossrefs

Sequence in context: A158369 A366067 A232888 * A107550 A097768 A286233

Adjacent sequences: A035751 A035752 A035753 * A035755 A035756 A035757

Keyword

nonn,easy

Author

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

Extensions

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

Status

approved