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A035906
Coordination sequence for diamond structure D^+_60. (Edges defined by l_1 norm = 1.)
1
1, 0, 7200, 0, 8644800, 0, 4158723680, 0, 1074729932160, 0, 173483353200288, 0, 19187724061887040, 0, 1548407735451345120, 0, 95421058074344344320, 0, 4648998863987510065440, 0, 184032053624967973166016, 0, 6051292765125604899742560, 0, 168331474188275017301655680, 0, 4022814049902922327686276000, 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=60.
CROSSREFS
Sequence in context: A064979 A348807 A204480 * A190114 A239566 A236993
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