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A035918
Coordination sequence for diamond structure D^+_84. (Edges defined by l_1 norm = 1.)
1
1, 0, 14112, 0, 33200832, 0, 31270754144, 0, 15800653486464, 0, 4977542380850592, 0, 1071822174138228800, 0, 167907946699820252640, 0, 20019527493762044941056, 0, 1879888501280846931938336, 0, 142817619730269235112367552, 0, 8970769855376398766776261728, 0, 474302047496125216885843184768, 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=84.
CROSSREFS
Sequence in context: A253796 A237153 A066698 * A157786 A186834 A263911
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