login
A035917
Coordination sequence for diamond structure D^+_82. (Edges defined by l_1 norm = 1.)
1
1, 0, 13448, 0, 30150416, 0, 27063010712, 0, 13032761962016, 0, 3913291362389672, 0, 803284881791282480, 0, 119978383321782198200, 0, 13641020048513471601728, 0, 1221725104670456390191304, 0, 88546015593657513545141072, 0, 5307256748692946318313380312, 0, 267833718693896594307599764064, 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=82.
CROSSREFS
Sequence in context: A323992 A157506 A238176 * A332387 A183676 A204394
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