A035887 Coordination sequence for diamond structure D^+_22. (Edges defined by l_1 norm = 1.)

1, 0, 968, 0, 156816, 0, 10286936, 0, 368804128, 0, 8453107432, 2097152, 136631618992, 530579456, 1668180181624, 26528972800, 16189344891456, 620777963520, 129752349166088, 9001280471040, 883945662928592

Offset

0,3

Links

Ray Chandler, Table of n, a(n) for n = 0..1000

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.

Index entries for linear recurrences with constant coefficients, signature (0, 22, 0, -231, 0, 1540, 0, -7315, 0, 26334, 0, -74613, 0, 170544, 0, -319770, 0, 497420, 0, -646646, 0, 705432, 0, -646646, 0, 497420, 0, -319770, 0, 170544, 0, -74613, 0, 26334, 0, -7315, 0, 1540, 0, -231, 0, 22, 0, -1).

Maple

f := proc(m) local k, t1; t1 := 2^(n-1)*binomial((n+2*m)/2-1, n-1); if m mod 2 = 0 then t1 := t1+add(2^k*binomial(n, k)*binomial(m-1, k-1), k=0..n); fi; t1; end; where n=22.

Crossrefs

Sequence in context: A246477 A064258 A142378 * A255656 A035759 A107555

Adjacent sequences: A035884 A035885 A035886 * A035888 A035889 A035890

Keyword

nonn

Author

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

Extensions

Recomputed by N. J. A. Sloane, Nov 27 1998

Status

approved