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A035886 Coordination sequence for diamond structure D^+_20. (Edges defined by l_1 norm = 1.) 0
1, 0, 800, 0, 107200, 0, 5831520, 0, 174074240, 0, 3340028320, 10485760, 45553842240, 807403520, 474040586720, 22284337152, 3959316509440, 344876646400, 27528013314080, 3621204787200, 163698115739072 (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=20.

CROSSREFS

Sequence in context: A045261 A101039 A121642 * A283899 A043404 A015065

Adjacent sequences:  A035883 A035884 A035885 * A035887 A035888 A035889

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 October 24 10:03 EDT 2021. Contains 348225 sequences. (Running on oeis4.)