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A035908
Coordination sequence for diamond structure D^+_64. (Edges defined by l_1 norm = 1.)
1
1, 0, 8192, 0, 11190272, 0, 6123315200, 0, 1799375912960, 0, 330122643283968, 0, 41474426978451456, 0, 3799040291725172736, 0, 265525958014053580800, 0, 14658590810928715735040, 0, 656823409555679115329536, 0, 24419567601184961681907712, 0, 767124041999543604847869952, 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=64.
CROSSREFS
Sequence in context: A069414 A289477 A222527 * A069274 A220585 A305756
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