%I #12 Jul 01 2018 08:38:56

%S 1,16,128,688,2944,10448,31616,83824,199424,434064,877696,1668656,

%T 3011200,5196880,8630144,13858544,21607936,32823056,48713856,70807984,

%U 101009792,141666256,195640192,266391152,358064384,475588240,624780416,812463408,1046589568

%N L1-coordination sequence for E_8 lattice in Construction A version of the lattice.

%H Colin Barker, <a href="/A045651/b045651.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_08">Index entries for linear recurrences with constant coefficients</a>, signature (8,-28,56,-70,56,-28,8,-1).

%F [ Sum_{i=1..min(8, n)} 2^8 * C(8, i) * C(n-1, i-1) ] + [ 2^(8-1)*C((((8+2n)/2)-1), 8-1) ].

%F G.f.: (x^8 + 8*x^7 + 28*x^6 + 56*x^5 + 198*x^4 + 56*x^3 + 28*x^2 + 8*x + 1) / (x-1)^8. - _Colin Barker_, Mar 04 2015

%o (PARI) Vec((x^8+8*x^7+28*x^6+56*x^5+198*x^4+56*x^3+28*x^2+8*x+1)/(x-1)^8 + O(x^100)) \\ _Colin Barker_, Mar 04 2015

%K easy,nonn

%O 0,2

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