A035764 - OEIS

%I #21 Sep 06 2023 01:50:43

%S 1,1458,355266,34910514,1862598402,62980925490,1485715581378,

%T 26117059455666,359014421036034,4003976643221682,37296107457684930,

%U 297019427057955378,2061520089784186626,12670725992539608882,69896490055937220546,350024151452942174130,1606812447909933740034

%N Coordination sequence for C_27 lattice.

%H Seiichi Manyama, <a href="/A035764/b035764.txt">Table of n, a(n) for n = 0..10000</a>

%H R. Bacher, P. de la Harpe and B. Venkov, <a href="http://dx.doi.org/10.1016/S0764-4442(97)83542-2">Séries de croissance et séries d'Ehrhart associées aux réseaux de racines</a>, C. R. Acad. Sci. Paris, 325 (Series 1) (1997), 1137-1142.

%H J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (<a href="http://neilsloane.com/doc/Me220.pdf">pdf</a>).

%H Joan Serra-Sagrista, <a href="http://dx.doi.org/10.1016/S0020-0190(00)00119-8">Enumeration of lattice points in l_1 norm</a>, Inf. Proc. Lett. 76 (1-2) (2000) 39-44.

%F a(n) = [x^(2n)] ((1+x)/(1-x))^27.

%K nonn,easy

%O 0,2

%A Joan Serra-Sagrista (jserra(AT)ccd.uab.es)

%E Recomputed by _N. J. A. Sloane_, Nov 25 1998