Properties

Label 640.2.o
Level $640$
Weight $2$
Character orbit 640.o
Rep. character $\chi_{640}(63,\cdot)$
Character field $\Q(\zeta_{4})$
Dimension $48$
Newform subspaces $11$
Sturm bound $192$
Trace bound $13$

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Defining parameters

Level: \( N \) \(=\) \( 640 = 2^{7} \cdot 5 \)
Weight: \( k \) \(=\) \( 2 \)
Character orbit: \([\chi]\) \(=\) 640.o (of order \(4\) and degree \(2\))
Character conductor: \(\operatorname{cond}(\chi)\) \(=\) \( 40 \)
Character field: \(\Q(i)\)
Newform subspaces: \( 11 \)
Sturm bound: \(192\)
Trace bound: \(13\)
Distinguishing \(T_p\): \(3\), \(7\), \(13\)

Dimensions

The following table gives the dimensions of various subspaces of \(M_{2}(640, [\chi])\).

Total New Old
Modular forms 224 48 176
Cusp forms 160 48 112
Eisenstein series 64 0 64

Trace form

\( 48 q + O(q^{10}) \) \( 48 q - 16 q^{17} + 16 q^{25} + 16 q^{65} - 48 q^{73} + 16 q^{81} + 80 q^{97} + O(q^{100}) \)

Decomposition of \(S_{2}^{\mathrm{new}}(640, [\chi])\) into newform subspaces

Label Char Prim Dim $A$ Field CM Minimal twist Traces Sato-Tate $q$-expansion
$a_{2}$ $a_{3}$ $a_{5}$ $a_{7}$
640.2.o.a 640.o 40.k $2$ $5.110$ \(\Q(\sqrt{-1}) \) None 640.2.o.a \(0\) \(-4\) \(-4\) \(-4\) $\mathrm{SU}(2)[C_{4}]$ \(q+(-2+2i)q^{3}+(-2+i)q^{5}+(-2+\cdots)q^{7}+\cdots\)
640.2.o.b 640.o 40.k $2$ $5.110$ \(\Q(\sqrt{-1}) \) None 640.2.o.a \(0\) \(-4\) \(4\) \(4\) $\mathrm{SU}(2)[C_{4}]$ \(q+(-2+2i)q^{3}+(2-i)q^{5}+(2-2i)q^{7}+\cdots\)
640.2.o.c 640.o 40.k $2$ $5.110$ \(\Q(\sqrt{-1}) \) \(\Q(\sqrt{-1}) \) 640.2.o.c \(0\) \(0\) \(-4\) \(0\) $\mathrm{U}(1)[D_{4}]$ \(q+(-2+i)q^{5}+3iq^{9}+(-5-5i)q^{13}+\cdots\)
640.2.o.d 640.o 40.k $2$ $5.110$ \(\Q(\sqrt{-1}) \) \(\Q(\sqrt{-1}) \) 640.2.o.d \(0\) \(0\) \(-4\) \(0\) $\mathrm{U}(1)[D_{4}]$ \(q+(-2-i)q^{5}+3iq^{9}+(1+i)q^{13}+\cdots\)
640.2.o.e 640.o 40.k $2$ $5.110$ \(\Q(\sqrt{-1}) \) \(\Q(\sqrt{-1}) \) 640.2.o.d \(0\) \(0\) \(4\) \(0\) $\mathrm{U}(1)[D_{4}]$ \(q+(2+i)q^{5}+3iq^{9}+(-1-i)q^{13}+\cdots\)
640.2.o.f 640.o 40.k $2$ $5.110$ \(\Q(\sqrt{-1}) \) \(\Q(\sqrt{-1}) \) 640.2.o.c \(0\) \(0\) \(4\) \(0\) $\mathrm{U}(1)[D_{4}]$ \(q+(2-i)q^{5}+3iq^{9}+(5+5i)q^{13}+\cdots\)
640.2.o.g 640.o 40.k $2$ $5.110$ \(\Q(\sqrt{-1}) \) None 640.2.o.a \(0\) \(4\) \(-4\) \(4\) $\mathrm{SU}(2)[C_{4}]$ \(q+(2-2i)q^{3}+(-2+i)q^{5}+(2-2i)q^{7}+\cdots\)
640.2.o.h 640.o 40.k $2$ $5.110$ \(\Q(\sqrt{-1}) \) None 640.2.o.a \(0\) \(4\) \(4\) \(-4\) $\mathrm{SU}(2)[C_{4}]$ \(q+(2-2i)q^{3}+(2-i)q^{5}+(-2+2i)q^{7}+\cdots\)
640.2.o.i 640.o 40.k $8$ $5.110$ 8.0.40960000.1 None 640.2.o.i \(0\) \(0\) \(0\) \(0\) $\mathrm{SU}(2)[C_{4}]$ \(q-\beta _{1}q^{3}-\beta _{5}q^{5}+\beta _{2}q^{7}+\beta _{3}q^{9}+\cdots\)
640.2.o.j 640.o 40.k $12$ $5.110$ 12.0.\(\cdots\).1 None 640.2.o.j \(0\) \(0\) \(0\) \(0\) $\mathrm{SU}(2)[C_{4}]$ \(q+\beta _{2}q^{3}+\beta _{3}q^{5}+\beta _{1}q^{7}+(\beta _{5}+\beta _{7}+\cdots)q^{9}+\cdots\)
640.2.o.k 640.o 40.k $12$ $5.110$ 12.0.\(\cdots\).1 None 640.2.o.j \(0\) \(0\) \(0\) \(0\) $\mathrm{SU}(2)[C_{4}]$ \(q+\beta _{2}q^{3}-\beta _{3}q^{5}-\beta _{1}q^{7}+(\beta _{5}+\beta _{7}+\cdots)q^{9}+\cdots\)

Decomposition of \(S_{2}^{\mathrm{old}}(640, [\chi])\) into lower level spaces

\( S_{2}^{\mathrm{old}}(640, [\chi]) \simeq \) \(S_{2}^{\mathrm{new}}(40, [\chi])\)\(^{\oplus 5}\)\(\oplus\)\(S_{2}^{\mathrm{new}}(80, [\chi])\)\(^{\oplus 4}\)\(\oplus\)\(S_{2}^{\mathrm{new}}(160, [\chi])\)\(^{\oplus 3}\)\(\oplus\)\(S_{2}^{\mathrm{new}}(320, [\chi])\)\(^{\oplus 2}\)