A035904 Coordination sequence for diamond structure D^+_56. (Edges defined by l_1 norm = 1.)

1, 0, 6272, 0, 6560512, 0, 2750165376, 0, 619570628096, 0, 87234261025408, 0, 8421733435019520, 0, 593725756425591680, 0, 31996344144606628864, 0, 1364769891317433896064, 0, 47356161580663828825856, 0, 1366783265864821578917248, 0, 33420445471923170953302528, 0, 703130505924510999473075840, 0

Offset

0,3

Links

Georg Fischer, Table of n, a(n) for n = 0..200

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.

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=56.

Crossrefs

Sequence in context: A195524 A045187 A223465 * A234440 A254635 A189655

Adjacent sequences: A035901 A035902 A035903 * A035905 A035906 A035907

Keyword

nonn

Author

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

Extensions

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

Zeroes inserted by Georg Fischer, Jul 26 2020

Status

approved