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A035775
Coordination sequence for C_38 lattice.
1
1, 2888, 1392016, 269493720, 28142347040, 1846012202088, 83558656596144, 2782948528883448, 71467464065517120, 1466676453767667080, 24743395759941243856, 351105989545855146008, 4270772766808101054816
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))^38.
MAPLE
c:=38: seq(coeff(series(((1+x)/(1-x))^c, x, n+1), x, n), n=0..30, 2); # Muniru A Asiru, Jul 01 2018
CROSSREFS
Sequence in context: A241529 A185502 A035895 * A107571 A072016 A253402
KEYWORD
nonn,easy
AUTHOR
Joan Serra-Sagrista (jserra(AT)ccd.uab.es)
EXTENSIONS
Recomputed by N. J. A. Sloane, Nov 25 1998
STATUS
approved