\(\Lambda_{\mathfrak{G}_{48}}(-1) \to \Lambda_{24}\)
Column \(j\) of each matrix gives \(\varphi(e_j)\) in the chosen basis of the target; the subdivisions separate orthogonal summands of the source (columns) and of the target (rows).
Notes
The coinvariant lattice of lattices[6,15] of Höhn and
Mason, arXiv:1505.06420, in the Leech lattice.
latticedb check computes this map again from
sources/hoehn_mason/lattices_6_15.json with
latticedb.hoehn_mason.embedding.
\(\Lambda_{\mathfrak{G}_{48}}(-1) \hookrightarrow \Lambda_{24}\)
The coinvariant lattice \(A\) of lattices[6,15] of Höhn and Mason, arXiv:1505.06420: the orthogonal complement in the Leech lattice of the fixed-point lattice \(B\) of rank 6.
\[\left(\begin{array}{rrrrrrrrrrrrrrrrrr}
1 & 2 & 1 & 1 & -6 & -5 & 2 & 4 & 3 & -5 & 4 & -6 & 2 & 2 & 3 & 2 & 2 & -6 \\
1 & 0 & 0 & 1 & 2 & 2 & 0 & -1 & -2 & 1 & -1 & 1 & 0 & -1 & 0 & -1 & -2 & 1 \\
1 & -1 & 0 & 1 & 1 & 1 & -1 & -2 & -2 & 2 & -1 & 2 & -1 & -1 & 0 & -1 & -2 & 2 \\
0 & 0 & 0 & 0 & 1 & 2 & -1 & -1 & -1 & 1 & -1 & 2 & -1 & -1 & 0 & -1 & -1 & 1 \\
-2 & -1 & -1 & -2 & 3 & 2 & 0 & -2 & 1 & 1 & -1 & 2 & -1 & 0 & -2 & 1 & 1 & 2 \\
1 & 1 & 0 & 0 & 1 & 1 & 0 & 0 & -1 & 0 & 0 & 0 & 1 & -1 & -1 & -1 & -1 & 1 \\
1 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & -1 & -1 & 0 & -1 & 1 & -2 & 1 & 0 & -2 & 1 \\
-3 & -3 & -1 & -1 & 1 & -1 & 0 & -1 & 2 & 2 & -1 & 2 & -2 & 3 & -1 & 1 & 3 & 0 \\
-3 & -1 & -1 & -3 & 2 & 2 & -1 & -1 & 2 & 2 & -1 & 2 & -1 & 1 & -3 & 1 & 2 & 3 \\
0 & -1 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & -1 & 1 & -1 & 1 & -1 & -1 & 0 & 1 \\
0 & 0 & 1 & 0 & 0 & 1 & -1 & 0 & 0 & 1 & -1 & 1 & -1 & 0 & -1 & -1 & 0 & 1 \\
-1 & 0 & -1 & -1 & 0 & -1 & 1 & 0 & 1 & -1 & 1 & -1 & 1 & 0 & 0 & 2 & 1 & -1 \\
-2 & 0 & -1 & -2 & 1 & 1 & -1 & -1 & 1 & 0 & -1 & 1 & 0 & 0 & -2 & 1 & 1 & 1 \\
1 & 1 & 1 & 1 & -2 & -1 & 0 & 1 & 0 & -1 & 1 & -1 & 0 & -1 & 2 & 0 & -1 & -1 \\
1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & -1 & 0 & 0 & -1 & 1 & 0 & 1 & -1 & 0 & -1 \\
2 & 0 & 1 & 2 & 0 & 0 & 0 & 0 & -2 & 1 & 0 & 0 & 0 & -1 & 1 & -1 & -2 & 0 \\
-1 & 0 & 0 & -1 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 0 & 0 & 0 & -1 & 0 & 1 & 1 \\
1 & 2 & 0 & 0 & -1 & 0 & 0 & 1 & -1 & -2 & 1 & -1 & 1 & -2 & 1 & 0 & -1 & -1 \\
1 & 0 & 0 & 1 & -1 & -1 & 0 & 0 & -1 & -1 & 0 & -1 & 1 & 0 & 1 & 0 & -1 & -1 \\
0 & -1 & 0 & 1 & 0 & 0 & -1 & -1 & -1 & 1 & -1 & 2 & -1 & 1 & 0 & -1 & 0 & 0 \\
1 & 2 & 1 & 0 & -2 & -1 & 0 & 2 & 1 & -2 & 1 & -3 & 1 & 0 & 0 & 0 & 0 & -1 \\
0 & -2 & 0 & 1 & 1 & 0 & 0 & -1 & -1 & 2 & -1 & 2 & -1 & 1 & 0 & -1 & 0 & 0 \\
0 & -1 & 0 & 1 & 1 & 0 & 0 & -1 & -1 & 1 & 0 & 2 & -1 & 0 & 1 & 0 & 0 & 0 \\
-1 & 2 & 0 & -3 & -1 & 1 & 0 & 1 & 3 & -2 & 1 & -2 & 1 & 0 & -2 & 1 & 1 & 1 \\
\end{array}\right)\]
{"matrix": [
[1, 2, 1, 1, -6, -5, 2, 4, 3, -5, 4, -6, 2, 2, 3, 2, 2, -6],
[1, 0, 0, 1, 2, 2, 0, -1, -2, 1, -1, 1, 0, -1, 0, -1, -2, 1],
[1, -1, 0, 1, 1, 1, -1, -2, -2, 2, -1, 2, -1, -1, 0, -1, -2, 2],
[0, 0, 0, 0, 1, 2, -1, -1, -1, 1, -1, 2, -1, -1, 0, -1, -1, 1],
[-2, -1, -1, -2, 3, 2, 0, -2, 1, 1, -1, 2, -1, 0, -2, 1, 1, 2],
[1, 1, 0, 0, 1, 1, 0, 0, -1, 0, 0, 0, 1, -1, -1, -1, -1, 1],
[1, 1, 0, 0, 0, 0, 0, 0, -1, -1, 0, -1, 1, -2, 1, 0, -2, 1],
[-3, -3, -1, -1, 1, -1, 0, -1, 2, 2, -1, 2, -2, 3, -1, 1, 3, 0],
[-3, -1, -1, -3, 2, 2, -1, -1, 2, 2, -1, 2, -1, 1, -3, 1, 2, 3],
[0, -1, 0, 0, 1, 0, 0, 0, 0, 1, -1, 1, -1, 1, -1, -1, 0, 1],
[0, 0, 1, 0, 0, 1, -1, 0, 0, 1, -1, 1, -1, 0, -1, -1, 0, 1],
[-1, 0, -1, -1, 0, -1, 1, 0, 1, -1, 1, -1, 1, 0, 0, 2, 1, -1],
[-2, 0, -1, -2, 1, 1, -1, -1, 1, 0, -1, 1, 0, 0, -2, 1, 1, 1],
[1, 1, 1, 1, -2, -1, 0, 1, 0, -1, 1, -1, 0, -1, 2, 0, -1, -1],
[1, 0, 0, 1, 0, 0, 1, 1, -1, 0, 0, -1, 1, 0, 1, -1, 0, -1],
[2, 0, 1, 2, 0, 0, 0, 0, -2, 1, 0, 0, 0, -1, 1, -1, -2, 0],
[-1, 0, 0, -1, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, -1, 0, 1, 1],
[1, 2, 0, 0, -1, 0, 0, 1, -1, -2, 1, -1, 1, -2, 1, 0, -1, -1],
[1, 0, 0, 1, -1, -1, 0, 0, -1, -1, 0, -1, 1, 0, 1, 0, -1, -1],
[0, -1, 0, 1, 0, 0, -1, -1, -1, 1, -1, 2, -1, 1, 0, -1, 0, 0],
[1, 2, 1, 0, -2, -1, 0, 2, 1, -2, 1, -3, 1, 0, 0, 0, 0, -1],
[0, -2, 0, 1, 1, 0, 0, -1, -1, 2, -1, 2, -1, 1, 0, -1, 0, 0],
[0, -1, 0, 1, 1, 0, 0, -1, -1, 1, 0, 2, -1, 0, 1, 0, 0, 0],
[-1, 2, 0, -3, -1, 1, 0, 1, 3, -2, 1, -2, 1, 0, -2, 1, 1, 1]
],
"row_subdivisions": [],
"column_subdivisions": []}