Defining parameters
Level: | \( N \) | \(=\) | \( 8 = 2^{3} \) |
Weight: | \( k \) | \(=\) | \( 21 \) |
Character orbit: | \([\chi]\) | \(=\) | 8.d (of order \(2\) and degree \(1\)) |
Character conductor: | \(\operatorname{cond}(\chi)\) | \(=\) | \( 8 \) |
Character field: | \(\Q\) | ||
Newform subspaces: | \( 2 \) | ||
Sturm bound: | \(21\) | ||
Trace bound: | \(1\) | ||
Distinguishing \(T_p\): | \(3\) |
Dimensions
The following table gives the dimensions of various subspaces of \(M_{21}(8, [\chi])\).
Total | New | Old | |
---|---|---|---|
Modular forms | 21 | 21 | 0 |
Cusp forms | 19 | 19 | 0 |
Eisenstein series | 2 | 2 | 0 |
Trace form
Decomposition of \(S_{21}^{\mathrm{new}}(8, [\chi])\) into newform subspaces
Label | Dim | $A$ | Field | CM | Traces | $q$-expansion | |||
---|---|---|---|---|---|---|---|---|---|
$a_{2}$ | $a_{3}$ | $a_{5}$ | $a_{7}$ | ||||||
8.21.d.a | $1$ | $20.281$ | \(\Q\) | \(\Q(\sqrt{-2}) \) | \(1024\) | \(114226\) | \(0\) | \(0\) | \(q+2^{10}q^{2}+114226q^{3}+2^{20}q^{4}+\cdots\) |
8.21.d.b | $18$ | $20.281$ | \(\mathbb{Q}[x]/(x^{18} + \cdots)\) | None | \(-398\) | \(-114228\) | \(0\) | \(0\) | \(q+(-22+\beta _{1})q^{2}+(-6347-5\beta _{1}+\cdots)q^{3}+\cdots\) |