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A035787
Coordination sequence for C_50 lattice.
6
1, 5000, 4170000, 1394447000, 250799764000, 28222682700200, 2180706863326000, 123252789641763000, 5335428332027176000, 183203070393610797000, 5129723834328569406800, 119780004243882975543000, 2376073555319729124284000, 40672867087351099089831400
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))^50.
CROSSREFS
Cf. A035745.
Sequence in context: A200910 A035901 A203919 * A108011 A018188 A280879
KEYWORD
nonn,easy
AUTHOR
Joan Serra-Sagrista (jserra(AT)ccd.uab.es)
EXTENSIONS
Recomputed by N. J. A. Sloane, Nov 25 1998
STATUS
approved