Defining parameters
| Level: | \( N \) | \(=\) | \( 27 = 3^{3} \) |
| Weight: | \( k \) | \(=\) | \( 4 \) |
| Character orbit: | \([\chi]\) | \(=\) | 27.a (trivial) |
| Character field: | \(\Q\) | ||
| Newform subspaces: | \( 3 \) | ||
| Sturm bound: | \(12\) | ||
| Trace bound: | \(2\) | ||
| Distinguishing \(T_p\): | \(2\) |
Dimensions
The following table gives the dimensions of various subspaces of \(M_{4}(\Gamma_0(27))\).
| Total | New | Old | |
|---|---|---|---|
| Modular forms | 12 | 4 | 8 |
| Cusp forms | 6 | 4 | 2 |
| Eisenstein series | 6 | 0 | 6 |
The following table gives the dimensions of the cuspidal new subspaces with specified eigenvalues for the Atkin-Lehner operators and the Fricke involution.
| \(3\) | Total | Cusp | Eisenstein | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| All | New | Old | All | New | Old | All | New | Old | ||||
| \(+\) | \(7\) | \(3\) | \(4\) | \(4\) | \(3\) | \(1\) | \(3\) | \(0\) | \(3\) | |||
| \(-\) | \(5\) | \(1\) | \(4\) | \(2\) | \(1\) | \(1\) | \(3\) | \(0\) | \(3\) | |||
Trace form
Decomposition of \(S_{4}^{\mathrm{new}}(\Gamma_0(27))\) into newform subspaces
| Label | Dim | $A$ | Field | CM | Traces | A-L signs | $q$-expansion | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| $a_{2}$ | $a_{3}$ | $a_{5}$ | $a_{7}$ | 3 | |||||||
| 27.4.a.a | $1$ | $1.593$ | \(\Q\) | None | \(-3\) | \(0\) | \(-15\) | \(-25\) | $-$ | \(q-3q^{2}+q^{4}-15q^{5}-5^{2}q^{7}+21q^{8}+\cdots\) | |
| 27.4.a.b | $1$ | $1.593$ | \(\Q\) | None | \(3\) | \(0\) | \(15\) | \(-25\) | $+$ | \(q+3q^{2}+q^{4}+15q^{5}-5^{2}q^{7}-21q^{8}+\cdots\) | |
| 27.4.a.c | $2$ | $1.593$ | \(\Q(\sqrt{2}) \) | None | \(0\) | \(0\) | \(0\) | \(22\) | $+$ | \(q+\beta q^{2}+10q^{4}-4\beta q^{5}+11q^{7}+2\beta q^{8}+\cdots\) | |
Decomposition of \(S_{4}^{\mathrm{old}}(\Gamma_0(27))\) into lower level spaces
\( S_{4}^{\mathrm{old}}(\Gamma_0(27)) \simeq \) \(S_{4}^{\mathrm{new}}(\Gamma_0(9))\)\(^{\oplus 2}\)