A035915 Coordination sequence for diamond structure D^+_78. (Edges defined by l_1 norm = 1.)

1, 0, 12168, 0, 24684816, 0, 20050650776, 0, 8739210543648, 0, 2375502273471912, 0, 441550716354149168, 0, 59738920517881797816, 0, 6154813102726791038016, 0, 499745917657668459264968, 0, 32852573414724334471351632, 0, 1787037602269852702724731608, 0, 81893843128627116973312755296, 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=78.

Crossrefs

Sequence in context: A013819 A227297 A013908 * A104791 A338950 A204873

Adjacent sequences: A035912 A035913 A035914 * A035916 A035917 A035918

Keyword

nonn

Author

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

Extensions

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

Zeros inserted by Georg Fischer, Jul 26 2020

Status

approved