A035925 - OEIS

A035925

Coordination sequence for diamond structure D^+_98. (Edges defined by l_1 norm = 1.)

1, 0, 19208, 0, 61504016, 0, 78823543064, 0, 54174273131552, 0, 23200998588819240, 0, 6787317128471047728, 0, 1443372362804937698616, 0, 233388899309424919685184, 0, 29689738444840209923490632, 0, 3051938054812173149666009680, 0, 259036036508584517068200003928, 0, 18479335956288173020817263098976, 0

(list; graph; refs; listen; history; text; internal format)

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=98.

CROSSREFS

Sequence in context: A184196 A210316 A323966 * A186875 A251803 A184667

Adjacent sequences: A035922 A035923 A035924 * A035926 A035927 A035928

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