Defining parameters
| Level: | \( N \) | = | \( 5 \) |
| Weight: | \( k \) | = | \( 18 \) |
| Nonzero newspaces: | \( 2 \) | ||
| Newform subspaces: | \( 3 \) | ||
| Sturm bound: | \(36\) | ||
| Trace bound: | \(1\) |
Dimensions
The following table gives the dimensions of various subspaces of \(M_{18}(\Gamma_1(5))\).
| Total | New | Old | |
|---|---|---|---|
| Modular forms | 19 | 15 | 4 |
| Cusp forms | 15 | 13 | 2 |
| Eisenstein series | 4 | 2 | 2 |
Trace form
Decomposition of \(S_{18}^{\mathrm{new}}(\Gamma_1(5))\)
We only show spaces with even 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 |
|---|---|---|---|---|
| 5.18.a | \(\chi_{5}(1, \cdot)\) | 5.18.a.a | 2 | 1 |
| 5.18.a.b | 3 | |||
| 5.18.b | \(\chi_{5}(4, \cdot)\) | 5.18.b.a | 8 | 1 |
Decomposition of \(S_{18}^{\mathrm{old}}(\Gamma_1(5))\) into lower level spaces
\( S_{18}^{\mathrm{old}}(\Gamma_1(5)) \cong \) \(S_{18}^{\mathrm{new}}(\Gamma_1(1))\)\(^{\oplus 2}\)