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 A029681 Theta series of quadratic form with Gram matrix [ 2, 1, 0; 1, 2, 1; 0, 1, 3 ]. 2

%I

%S 1,0,6,6,0,6,6,12,6,0,6,12,6,6,24,12,0,0,18,6,6,14,12,24,6,0,18,24,12,

%T 12,12,12,6,0,12,42,0,12,30,12,6,0,42,12,12,18,12,36,6,0,30,12,6,24,

%U 24,12,24,0,24,30,12,6,36,60,0,0,12,24,0,12,42,36,18,0,24,30,6,48,36,12,6,0,24

%N Theta series of quadratic form with Gram matrix [ 2, 1, 0; 1, 2, 1; 0, 1, 3 ].

%C The Gram matrix [ 2, 1, 1; 1, 2, 1; 1, 1, 3 ] defines the same lattice.

%C This is the trigonal R lattice (the classical holotype) of dimension 3.

%H John Cannon, <a href="/A029681/b029681.txt">Table of n, a(n) for n = 0..9999</a>

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

%e 1 + 6*q^2 + 6*q^3 + 6*q^5 + 6*q^6 + 12*q^7 + 6*q^8 + 6*q^10 + 12*q^11 + 6*q^12 + ...

%K nonn

%O 0,3

%A _N. J. A. Sloane_.

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Last modified November 29 15:46 EST 2021. Contains 349416 sequences. (Running on oeis4.)