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Properties

Label 4.21.21.1.1
Class number $1$
Dimension $4$
Determinant $21$
Level $21$

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Lattice Invariants

Dimension:$4$
Determinant:$21$
Level:$21$
Density:$0.269215531233698123002851316577\dots$
Group order:$48$
Hermite number:$0.934275955456400218421595139034\dots$
Minimal vector length:$2$
Kissing number:$8$
Normalized minimal vectors: $(1, -1, 0, 0)$, $(1, 0, 0, 0)$, $(0, 1, 0, 0)$, $(0, 0, 1, 0)$
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Theta Series

\(1 \) \(\mathstrut +\mathstrut 8 q^{2} \) \(\mathstrut +\mathstrut 16 q^{4} \) \(\mathstrut +\mathstrut 30 q^{6} \) \(\mathstrut +\mathstrut 24 q^{8} \) \(\mathstrut +\mathstrut 72 q^{10} \) \(\mathstrut +\mathstrut 24 q^{12} \) \(\mathstrut +\mathstrut 50 q^{14} \) \(\mathstrut +\mathstrut 80 q^{16} \) \(\mathstrut +\mathstrut 104 q^{18} \) \(\mathstrut +\mathstrut 36 q^{20} \) \(\mathstrut +\mathstrut O(q^{21}) \)

Gram Matrix

$\left(\begin{array}{rrrr} 2 & 1 & 0 & 0 \\ 1 & 2 & 0 & 0 \\ 0 & 0 & 2 & 1 \\ 0 & 0 & 1 & 4 \end{array}\right)$

Genus Structure

Genus representatives:
Class number:$1$
 
$\left(\begin{array}{rrrr} 2 & 1 & 0 & 0 \\ 1 & 2 & 0 & 0 \\ 0 & 0 & 2 & 1 \\ 0 & 0 & 1 & 4 \end{array}\right)$
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