Defining parameters
| Level: | \( N \) | = | \( 8 = 2^{3} \) |
| Weight: | \( k \) | = | \( 5 \) |
| Nonzero newspaces: | \( 1 \) | ||
| Newform subspaces: | \( 2 \) | ||
| Sturm bound: | \(20\) | ||
| Trace bound: | \(0\) |
Dimensions
The following table gives the dimensions of various subspaces of \(M_{5}(\Gamma_1(8))\).
| Total | New | Old | |
|---|---|---|---|
| Modular forms | 11 | 5 | 6 |
| Cusp forms | 5 | 3 | 2 |
| Eisenstein series | 6 | 2 | 4 |
Trace form
Decomposition of \(S_{5}^{\mathrm{new}}(\Gamma_1(8))\)
We only show spaces with odd parity, since no modular forms exist when this condition is not satisfied. Within each space \( S_k^{\mathrm{new}}(N, \chi) \) we list available newforms together with their dimension.
| Label | \(\chi\) | Newforms | Dimension | \(\chi\) degree |
|---|---|---|---|---|
| 8.5.c | \(\chi_{8}(7, \cdot)\) | None | 0 | 1 |
| 8.5.d | \(\chi_{8}(3, \cdot)\) | 8.5.d.a | 1 | 1 |
| 8.5.d.b | 2 |
Decomposition of \(S_{5}^{\mathrm{old}}(\Gamma_1(8))\) into lower level spaces
\( S_{5}^{\mathrm{old}}(\Gamma_1(8)) \cong \) \(S_{5}^{\mathrm{new}}(\Gamma_1(1))\)\(^{\oplus 4}\)\(\oplus\)\(S_{5}^{\mathrm{new}}(\Gamma_1(2))\)\(^{\oplus 3}\)\(\oplus\)\(S_{5}^{\mathrm{new}}(\Gamma_1(4))\)\(^{\oplus 2}\)