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A035781
Coordination sequence for C_44 lattice.
1
1, 3872, 2501312, 648339296, 90488748416, 7914446636448, 476256430985280, 21013302552438240, 712041389847515904, 19196735036095030304, 423435066223344657856, 7816588576688121767008, 123043979986038246517888
OFFSET
0,2
LINKS
R. Bacher, P. de la Harpe and B. Venkov, Séries de croissance et séries d'Ehrhart associées aux réseaux de racines, C. R. Acad. Sci. Paris, 325 (Series 1) (1997), 1137-1142.
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.
FORMULA
a(n) = [x^(2n)] ((1+x)/(1-x))^44.
MAPLE
seq(coeff(series(((1+x)/(1-x))^44, x, n+1), x, n), n=0..30, 2); # Muniru A Asiru, Aug 12 2018
CROSSREFS
Cf. A035739.
Sequence in context: A249325 A249218 A264206 * A108005 A065696 A246735
KEYWORD
nonn,easy
AUTHOR
Joan Serra-Sagrista (jserra(AT)ccd.uab.es)
EXTENSIONS
Recomputed by N. J. A. Sloane, Nov 25 1998
STATUS
approved