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%I #14 Sep 05 2023 15:12:58
%S 1,100,5000,166700,4170000,83500020,1394447000,19980314300,
%T 250799764000,2802204288900,28222682700200,258862555329100,
%U 2180706863326000,16993705726247700,123252789641763000,836413142574501340
%N Coordination sequence for lattice D*_50 (with edges defined by l_1 norm = 1).
%C Differs from A035745 first at a(25), a(26), a(27), etc. - _R. J. Mathar_, Oct 24 2008
%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.
%H <a href="/index/Rec#order_50">Index entries for linear recurrences with constant coefficients</a>, signature (50, -1225, 19600, -230300, 2118760, -15890700, 99884400, -536878650, 2505433700, -10272278170, 37353738800, -121399651100, 354860518600, -937845656300, 2250829575120, -4923689695575, 9847379391150, -18053528883775, 30405943383200, -47129212243960, 67327446062800, -88749815264600, 108043253365600, -121548660036300, 126410606437752, -121548660036300, 108043253365600, -88749815264600, 67327446062800, -47129212243960, 30405943383200, -18053528883775, 9847379391150, -4923689695575, 2250829575120, -937845656300, 354860518600, -121399651100, 37353738800, -10272278170, 2505433700, -536878650, 99884400, -15890700, 2118760, -230300, 19600, -1225, 50, -1).
%F a(m) = (Sum_{k=0..n} 2^k*binomial(n, k)*binomial(m-1, k-1)) + 2^n*binomial((n+2*m)/2-1, n-1); with n=50.
%K nonn
%O 0,2
%A _N. J. A. Sloane_, J. Serra-Sagrista (jserra(AT)ccd.uab.es)
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