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A035916
Coordination sequence for diamond structure D^+_80. (Edges defined by l_1 norm = 1.)
1
1, 0, 12800, 0, 27315200, 0, 23338104320, 0, 10698844067840, 0, 3058431999744512, 0, 597778600580572160, 0, 85027230683021319680, 0, 9208060526880831549440, 0, 785696146272773983470080, 0, 54264336460274894557740032, 0, 3100237607076259583597381120, 0, 149174495875885415147284367360, 0
OFFSET
0,3
LINKS
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=80.
CROSSREFS
Sequence in context: A209091 A207133 A157509 * A243050 A246809 A204490
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