Defining parameters
Level: | \( N \) | = | \( 21 = 3 \cdot 7 \) |
Weight: | \( k \) | = | \( 3 \) |
Nonzero newspaces: | \( 4 \) | ||
Newform subspaces: | \( 7 \) | ||
Sturm bound: | \(96\) | ||
Trace bound: | \(2\) |
Dimensions
The following table gives the dimensions of various subspaces of \(M_{3}(\Gamma_1(21))\).
Total | New | Old | |
---|---|---|---|
Modular forms | 44 | 26 | 18 |
Cusp forms | 20 | 18 | 2 |
Eisenstein series | 24 | 8 | 16 |
Trace form
Decomposition of \(S_{3}^{\mathrm{new}}(\Gamma_1(21))\)
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 the newforms together with their dimension.
Decomposition of \(S_{3}^{\mathrm{old}}(\Gamma_1(21))\) into lower level spaces
\( S_{3}^{\mathrm{old}}(\Gamma_1(21)) \cong \) \(S_{3}^{\mathrm{new}}(\Gamma_1(7))\)\(^{\oplus 2}\)