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A035897 Coordination sequence for diamond structure D^+_42. (Edges defined by l_1 norm = 1.) 0
1, 0, 3528, 0, 2076816, 0, 490681688, 0, 62456027424, 0, 4985149915368, 0, 273998113272240, 0, 11053262513080440, 0, 342841481215636032, 0, 8471578904288191496, 0, 171504713146698879696, 2199023255552 (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..21.

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=42.

CROSSREFS

Sequence in context: A187726 A267125 A241240 * A064256 A232555 A035779

Adjacent sequences:  A035894 A035895 A035896 * A035898 A035899 A035900

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 January 27 08:31 EST 2020. Contains 331293 sequences. (Running on oeis4.)