Defining parameters
| Level: | \( N \) | \(=\) | \( 28 = 2^{2} \cdot 7 \) |
| Weight: | \( k \) | \(=\) | \( 2 \) |
| Character orbit: | \([\chi]\) | \(=\) | 28.a (trivial) |
| Character field: | \(\Q\) | ||
| Newform subspaces: | \( 0 \) | ||
| Sturm bound: | \(8\) | ||
| Trace bound: | \(0\) |
Dimensions
The following table gives the dimensions of various subspaces of \(M_{2}(\Gamma_0(28))\).
| Total | New | Old | |
|---|---|---|---|
| Modular forms | 7 | 0 | 7 |
| Cusp forms | 2 | 0 | 2 |
| Eisenstein series | 5 | 0 | 5 |
The following table gives the dimensions of the cuspidal new subspaces with specified eigenvalues for the Atkin-Lehner operators and the Fricke involution.
| \(2\) | \(7\) | Fricke | Total | Cusp | Eisenstein | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| All | New | Old | All | New | Old | All | New | Old | ||||||
| \(+\) | \(+\) | \(+\) | \(1\) | \(0\) | \(1\) | \(0\) | \(0\) | \(0\) | \(1\) | \(0\) | \(1\) | |||
| \(+\) | \(-\) | \(-\) | \(3\) | \(0\) | \(3\) | \(1\) | \(0\) | \(1\) | \(2\) | \(0\) | \(2\) | |||
| \(-\) | \(+\) | \(-\) | \(1\) | \(0\) | \(1\) | \(0\) | \(0\) | \(0\) | \(1\) | \(0\) | \(1\) | |||
| \(-\) | \(-\) | \(+\) | \(2\) | \(0\) | \(2\) | \(1\) | \(0\) | \(1\) | \(1\) | \(0\) | \(1\) | |||
| Plus space | \(+\) | \(3\) | \(0\) | \(3\) | \(1\) | \(0\) | \(1\) | \(2\) | \(0\) | \(2\) | ||||
| Minus space | \(-\) | \(4\) | \(0\) | \(4\) | \(1\) | \(0\) | \(1\) | \(3\) | \(0\) | \(3\) | ||||
Decomposition of \(S_{2}^{\mathrm{old}}(\Gamma_0(28))\) into lower level spaces
\( S_{2}^{\mathrm{old}}(\Gamma_0(28)) \simeq \) \(S_{2}^{\mathrm{new}}(\Gamma_0(14))\)\(^{\oplus 2}\)