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A035895 Coordination sequence for diamond structure D^+_38. (Edges defined by l_1 norm = 1.) 0
1, 0, 2888, 0, 1392016, 0, 269493720, 0, 28142347040, 0, 1846012202088, 0, 83558656596144, 0, 2782948528883448, 0, 71467464065517120, 0, 1466676453767667080, 137438953472, 24743400982621475792 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

REFERENCES

J. Serra-Sagrista, Enumeration of lattice points in l_1 norm, Information Processing Letters, 76, no. 1-2 (2000), 39-44.

LINKS

Table of n, a(n) for n=0..20.

J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (pdf).

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=38.

CROSSREFS

Sequence in context: A259403 A241529 A185502 * A035775 A107571 A072016

Adjacent sequences:  A035892 A035893 A035894 * A035896 A035897 A035898

KEYWORD

nonn

AUTHOR

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

EXTENSIONS

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

STATUS

approved

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Last modified June 22 03:25 EDT 2021. Contains 345367 sequences. (Running on oeis4.)