Defining parameters
Level: | \( N \) | \(=\) | \( 21 = 3 \cdot 7 \) |
Weight: | \( k \) | \(=\) | \( 7 \) |
Character orbit: | \([\chi]\) | \(=\) | 21.f (of order \(6\) and degree \(2\)) |
Character conductor: | \(\operatorname{cond}(\chi)\) | \(=\) | \( 7 \) |
Character field: | \(\Q(\zeta_{6})\) | ||
Newform subspaces: | \( 2 \) | ||
Sturm bound: | \(18\) | ||
Trace bound: | \(3\) | ||
Distinguishing \(T_p\): | \(2\) |
Dimensions
The following table gives the dimensions of various subspaces of \(M_{7}(21, [\chi])\).
Total | New | Old | |
---|---|---|---|
Modular forms | 36 | 16 | 20 |
Cusp forms | 28 | 16 | 12 |
Eisenstein series | 8 | 0 | 8 |
Trace form
Decomposition of \(S_{7}^{\mathrm{new}}(21, [\chi])\) into newform subspaces
Label | Dim | $A$ | Field | CM | Traces | $q$-expansion | |||
---|---|---|---|---|---|---|---|---|---|
$a_{2}$ | $a_{3}$ | $a_{5}$ | $a_{7}$ | ||||||
21.7.f.a | $8$ | $4.831$ | \(\mathbb{Q}[x]/(x^{8} - \cdots)\) | None | \(-5\) | \(-108\) | \(-294\) | \(-656\) | \(q+(-1-\beta _{1}+\beta _{2})q^{2}+(-18+9\beta _{2}+\cdots)q^{3}+\cdots\) |
21.7.f.b | $8$ | $4.831$ | \(\mathbb{Q}[x]/(x^{8} - \cdots)\) | None | \(-5\) | \(108\) | \(-42\) | \(748\) | \(q+(-\beta _{1}-\beta _{2})q^{2}+(9+9\beta _{2})q^{3}+(-43+\cdots)q^{4}+\cdots\) |
Decomposition of \(S_{7}^{\mathrm{old}}(21, [\chi])\) into lower level spaces
\( S_{7}^{\mathrm{old}}(21, [\chi]) \cong \) \(S_{7}^{\mathrm{new}}(7, [\chi])\)\(^{\oplus 2}\)