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Theta series of laminated lattice LAMBDA_23.
1

%I #13 Jun 29 2021 16:54:29

%S 1,0,93150,6476800,133204500,1384998912,9403968600,47406643200,

%T 192825064350,663509299200,2007834672456,5456580940800,13618454702600,

%U 31528851609600,68717357121600,141663767066624,279245882826900,527244094771200,961802512637350

%N Theta series of laminated lattice LAMBDA_23.

%C Theta series of the 23-dimensional sublattice of the Leech lattice orthogonal to any norm 4 vector

%D J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 174.

%H Andy Huchala, <a href="/A023945/b023945.txt">Table of n, a(n) for n = 0..20000</a>

%H G. Nebe and N. J. A. Sloane, <a href="http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/LAMBDA23.html">Home page for this lattice</a>

%o (Magma)

%o L := Lattice("Lambda", 23);

%o B := Basis(ThetaSeriesModularFormSpace(L), 20);

%o S := [1, 0, 93150, 6476800, 133204500, 1384998912, 9403968600, 47406643200, 192825064350, 663509299200, 2007834672456, 5456580940800];

%o Coefficients(&+[B[i] * S[i] : i in [1..12]]); // _Andy Huchala_, Jun 29 2021

%K nonn

%O 0,3

%A _N. J. A. Sloane_.

%E More terms from Kok Seng Chua (chuaks(AT)ihpc.nus.edu.sg), Sep 06 2001

%E a(17) - a(18) from _Andy Huchala_, Jun 29 2021