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A035925
Coordination sequence for diamond structure D^+_98. (Edges defined by l_1 norm = 1.)
1
1, 0, 19208, 0, 61504016, 0, 78823543064, 0, 54174273131552, 0, 23200998588819240, 0, 6787317128471047728, 0, 1443372362804937698616, 0, 233388899309424919685184, 0, 29689738444840209923490632, 0, 3051938054812173149666009680, 0, 259036036508584517068200003928, 0, 18479335956288173020817263098976, 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=98.
CROSSREFS
Sequence in context: A184196 A210316 A323966 * A186875 A251803 A184667
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