Properties

Label 20.3
Level 20
Weight 3
Dimension 10
Nonzero newspaces 3
Newform subspaces 5
Sturm bound 72
Trace bound 2

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Defining parameters

Level: \( N \) = \( 20 = 2^{2} \cdot 5 \)
Weight: \( k \) = \( 3 \)
Nonzero newspaces: \( 3 \)
Newform subspaces: \( 5 \)
Sturm bound: \(72\)
Trace bound: \(2\)

Dimensions

The following table gives the dimensions of various subspaces of \(M_{3}(\Gamma_1(20))\).

Total New Old
Modular forms 34 14 20
Cusp forms 14 10 4
Eisenstein series 20 4 16

Trace form

\( 10 q - 2 q^{2} + 2 q^{3} - 4 q^{4} - 10 q^{5} - 16 q^{6} - 14 q^{7} - 8 q^{8} - 8 q^{9} + 6 q^{10} + 20 q^{11} + 40 q^{12} + 2 q^{13} + 56 q^{14} + 2 q^{15} + 48 q^{16} - 22 q^{17} + 22 q^{18} - 44 q^{20}+ \cdots + 102 q^{98}+O(q^{100}) \) Copy content Toggle raw display

Decomposition of \(S_{3}^{\mathrm{new}}(\Gamma_1(20))\)

We only show spaces with odd parity, since no modular forms exist when this condition is not satisfied. Within each space \( S_k^{\mathrm{new}}(N, \chi) \) we list available newforms together with their dimension.

Label \(\chi\) Newforms Dimension \(\chi\) degree
20.3.b \(\chi_{20}(11, \cdot)\) 20.3.b.a 4 1
20.3.d \(\chi_{20}(19, \cdot)\) 20.3.d.a 1 1
20.3.d.b 1
20.3.d.c 2
20.3.f \(\chi_{20}(13, \cdot)\) 20.3.f.a 2 2

Decomposition of \(S_{3}^{\mathrm{old}}(\Gamma_1(20))\) into lower level spaces

\( S_{3}^{\mathrm{old}}(\Gamma_1(20)) \cong \) \(S_{3}^{\mathrm{new}}(\Gamma_1(1))\)\(^{\oplus 6}\)\(\oplus\)\(S_{3}^{\mathrm{new}}(\Gamma_1(2))\)\(^{\oplus 4}\)\(\oplus\)\(S_{3}^{\mathrm{new}}(\Gamma_1(4))\)\(^{\oplus 2}\)\(\oplus\)\(S_{3}^{\mathrm{new}}(\Gamma_1(5))\)\(^{\oplus 3}\)\(\oplus\)\(S_{3}^{\mathrm{new}}(\Gamma_1(10))\)\(^{\oplus 2}\)