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%I #24 Sep 05 2023 13:03:55
%S 1,24,288,2312,14016,68664,288096,1071912,3600768,11036504,31125408,
%T 81412680,199013440,457923960,998269920,2073758312,4126016256,
%U 7897561752,14598964768,26150436744,45523755456,77217221304,127904389728
%N Coordination sequence for lattice D*_12 (with edges defined by l_1 norm = 1).
%H Vincenzo Librandi, <a href="/A035475/b035475.txt">Table of n, a(n) for n = 0..1000</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.
%H <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (12, -66, 220, -495, 792, -924, 792, -495, 220, -66, 12, -1).
%F a(m)=add(2^k*binomial(n, k)*binomial(m-1, k-1), k=0..n)+2^n*binomial((n+2*m)/2-1, n-1); with n=12.
%F G.f.: (x^4+4*x^3+22*x^2+4*x+1)*(x^8+8*x^7+12*x^6-8*x^5+230*x^4-8*x^3+12*x^2+8*x+1) / (x-1)^12. - _Colin Barker_, Nov 20 2012
%t CoefficientList[Series[(x^4 + 4 x^3 + 22 x^2 + 4 x + 1) (x^8 + 8 x^7 + 12 x^6 - 8 x^5 + 230 x^4 - 8 x^3 + 12 x^2 + 8 x + 1)/(x - 1)^12, {x, 0, 30}], x] (* _Vincenzo Librandi_, Oct 21 2013 *)
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_, J. Serra-Sagrista (jserra(AT)ccd.uab.es)
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