Defining parameters
| Level: | \( N \) | \(=\) | \( 55 = 5 \cdot 11 \) |
| Weight: | \( k \) | \(=\) | \( 4 \) |
| Character orbit: | \([\chi]\) | \(=\) | 55.a (trivial) |
| Character field: | \(\Q\) | ||
| Newform subspaces: | \( 4 \) | ||
| Sturm bound: | \(24\) | ||
| Trace bound: | \(1\) | ||
| Distinguishing \(T_p\): | \(2\) |
Dimensions
The following table gives the dimensions of various subspaces of \(M_{4}(\Gamma_0(55))\).
| Total | New | Old | |
|---|---|---|---|
| Modular forms | 20 | 10 | 10 |
| Cusp forms | 16 | 10 | 6 |
| Eisenstein series | 4 | 0 | 4 |
The following table gives the dimensions of the cuspidal new subspaces with specified eigenvalues for the Atkin-Lehner operators and the Fricke involution.
| \(5\) | \(11\) | Fricke | Total | Cusp | Eisenstein | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| All | New | Old | All | New | Old | All | New | Old | ||||||
| \(+\) | \(+\) | \(+\) | \(7\) | \(3\) | \(4\) | \(6\) | \(3\) | \(3\) | \(1\) | \(0\) | \(1\) | |||
| \(+\) | \(-\) | \(-\) | \(3\) | \(1\) | \(2\) | \(2\) | \(1\) | \(1\) | \(1\) | \(0\) | \(1\) | |||
| \(-\) | \(+\) | \(-\) | \(5\) | \(2\) | \(3\) | \(4\) | \(2\) | \(2\) | \(1\) | \(0\) | \(1\) | |||
| \(-\) | \(-\) | \(+\) | \(5\) | \(4\) | \(1\) | \(4\) | \(4\) | \(0\) | \(1\) | \(0\) | \(1\) | |||
| Plus space | \(+\) | \(12\) | \(7\) | \(5\) | \(10\) | \(7\) | \(3\) | \(2\) | \(0\) | \(2\) | ||||
| Minus space | \(-\) | \(8\) | \(3\) | \(5\) | \(6\) | \(3\) | \(3\) | \(2\) | \(0\) | \(2\) | ||||
Trace form
Decomposition of \(S_{4}^{\mathrm{new}}(\Gamma_0(55))\) into newform subspaces
| Label | Dim | $A$ | Field | CM | Traces | A-L signs | $q$-expansion | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| $a_{2}$ | $a_{3}$ | $a_{5}$ | $a_{7}$ | 5 | 11 | |||||||
| 55.4.a.a | $1$ | $3.245$ | \(\Q\) | None | \(1\) | \(-3\) | \(-5\) | \(-9\) | $+$ | $-$ | \(q+q^{2}-3q^{3}-7q^{4}-5q^{5}-3q^{6}+\cdots\) | |
| 55.4.a.b | $2$ | $3.245$ | \(\Q(\sqrt{17}) \) | None | \(-7\) | \(-3\) | \(10\) | \(-25\) | $-$ | $+$ | \(q+(-3-\beta )q^{2}+(-1-\beta )q^{3}+(5+7\beta )q^{4}+\cdots\) | |
| 55.4.a.c | $3$ | $3.245$ | 3.3.568.1 | None | \(5\) | \(-3\) | \(-15\) | \(-15\) | $+$ | $+$ | \(q+(1+\beta _{1}-\beta _{2})q^{2}+(-2-3\beta _{2})q^{3}+\cdots\) | |
| 55.4.a.d | $4$ | $3.245$ | 4.4.1539480.1 | None | \(1\) | \(9\) | \(20\) | \(9\) | $-$ | $-$ | \(q+\beta _{1}q^{2}+(2-\beta _{2})q^{3}+(5+\beta _{1}+\beta _{3})q^{4}+\cdots\) | |
Decomposition of \(S_{4}^{\mathrm{old}}(\Gamma_0(55))\) into lower level spaces
\( S_{4}^{\mathrm{old}}(\Gamma_0(55)) \simeq \) \(S_{4}^{\mathrm{new}}(\Gamma_0(5))\)\(^{\oplus 2}\)\(\oplus\)\(S_{4}^{\mathrm{new}}(\Gamma_0(11))\)\(^{\oplus 2}\)