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A035849 Coordination sequence for A_23 lattice. 0
1, 552, 76452, 4756952, 169447302, 3956576472, 66087441092, 839584669992, 8489857618992, 70764981877592, 499828461729852, 3059000328006312, 16519884821277962, 79920498285116712, 350767245201478812 (list; graph; refs; listen; history; text; internal format)
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.
Index entries for linear recurrences with constant coefficients, signature (23, -253, 1771, -8855, 33649, -100947, 245157, -490314, 817190, -1144066, 1352078, -1352078, 1144066, -817190, 490314, -245157, 100947, -33649, 8855, -1771, 253, -23, 1).
FORMULA
Sum_{d=1..23} C(24, d)*C(m/2-1, d-1)*C(23-d+m/2, m/2), where norm m is always even.
CROSSREFS
Sequence in context: A282595 A290048 A023914 * A028686 A247531 A171428
KEYWORD
nonn,easy
AUTHOR
Joan Serra-Sagrista (jserra(AT)ccd.uab.es)
STATUS
approved

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Last modified June 16 19:52 EDT 2024. Contains 373432 sequences. (Running on oeis4.)