Properties

Label 840.2.u.b
Level $840$
Weight $2$
Character orbit 840.u
Analytic conductor $6.707$
Analytic rank $0$
Dimension $4$
CM discriminant -24
Inner twists $8$

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Newspace parameters

Copy content comment:Compute space of new eigenforms
 
Copy content gp:[N,k,chi] = [840,2,Mod(629,840)] mf = mfinit([N,k,chi],0) lf = mfeigenbasis(mf)
 
Copy content sage:from sage.modular.dirichlet import DirichletCharacter H = DirichletGroup(840, base_ring=CyclotomicField(2)) chi = DirichletCharacter(H, H._module([0, 1, 1, 1, 1])) N = Newforms(chi, 2, names="a")
 
Copy content magma://Please install CHIMP (https://github.com/edgarcosta/CHIMP) if you want to run this code chi := DirichletCharacter("840.629"); S:= CuspForms(chi, 2); N := Newforms(S);
 
Level: \( N \) \(=\) \( 840 = 2^{3} \cdot 3 \cdot 5 \cdot 7 \)
Weight: \( k \) \(=\) \( 2 \)
Character orbit: \([\chi]\) \(=\) 840.u (of order \(2\), degree \(1\), minimal)

Newform invariants

Copy content comment:select newform
 
Copy content sage:traces = [4,0,0,-8,0,0,4,0,12,8,0,0,0,0,12] f = next(g for g in N if [g.coefficient(i+1).trace() for i in range(15)] == traces)
 
Copy content gp:f = lf[1] \\ Warning: the index may be different
 
Self dual: no
Analytic conductor: \(6.70743376979\)
Analytic rank: \(0\)
Dimension: \(4\)
Coefficient field: \(\Q(\sqrt{-2}, \sqrt{3})\)
Copy content comment:defining polynomial
 
Copy content gp:f.mod \\ as an extension of the character field
 
Defining polynomial: \( x^{4} + 4x^{2} + 1 \) Copy content Toggle raw display
Coefficient ring: \(\Z[a_1, a_2, a_3]\)
Coefficient ring index: \( 2 \)
Twist minimal: yes
Sato-Tate group: $\mathrm{U}(1)[D_{2}]$

$q$-expansion

Copy content comment:q-expansion
 
Copy content sage:f.q_expansion() # note that sage often uses an isomorphic number field
 
Copy content gp:mfcoefs(f, 20)
 

Coefficients of the \(q\)-expansion are expressed in terms of a basis \(1,\beta_1,\beta_2,\beta_3\) for the coefficient ring described below. We also show the integral \(q\)-expansion of the trace form.

\(f(q)\) \(=\) \( q - \beta_1 q^{2} + \beta_{2} q^{3} - 2 q^{4} + (\beta_{2} + \beta_1) q^{5} - \beta_{3} q^{6} + (\beta_{3} + 1) q^{7} + 2 \beta_1 q^{8} + 3 q^{9} + ( - \beta_{3} + 2) q^{10} - 2 \beta_{2} q^{11} - 2 \beta_{2} q^{12}+ \cdots - 6 \beta_{2} q^{99}+O(q^{100}) \) Copy content Toggle raw display
\(\operatorname{Tr}(f)(q)\) \(=\) \( 4 q - 8 q^{4} + 4 q^{7} + 12 q^{9} + 8 q^{10} + 12 q^{15} + 16 q^{16} + 4 q^{25} - 8 q^{28} - 24 q^{33} - 24 q^{36} - 16 q^{40} + 24 q^{42} - 20 q^{49} - 24 q^{55} - 24 q^{60} + 12 q^{63} - 32 q^{64} + 32 q^{70}+ \cdots + 8 q^{97}+O(q^{100}) \) Copy content Toggle raw display

Basis of coefficient ring in terms of a root \(\nu\) of \( x^{4} + 4x^{2} + 1 \) : Copy content Toggle raw display

\(\beta_{1}\)\(=\) \( \nu^{3} + 3\nu \) Copy content Toggle raw display
\(\beta_{2}\)\(=\) \( \nu^{2} + 2 \) Copy content Toggle raw display
\(\beta_{3}\)\(=\) \( \nu^{3} + 5\nu \) Copy content Toggle raw display
\(\nu\)\(=\) \( ( \beta_{3} - \beta_1 ) / 2 \) Copy content Toggle raw display
\(\nu^{2}\)\(=\) \( \beta_{2} - 2 \) Copy content Toggle raw display
\(\nu^{3}\)\(=\) \( ( -3\beta_{3} + 5\beta_1 ) / 2 \) Copy content Toggle raw display

Character values

We give the values of \(\chi\) on generators for \(\left(\mathbb{Z}/840\mathbb{Z}\right)^\times\).

\(n\) \(241\) \(281\) \(337\) \(421\) \(631\)
\(\chi(n)\) \(-1\) \(-1\) \(-1\) \(-1\) \(1\)

Embeddings

For each embedding \(\iota_m\) of the coefficient field, the values \(\iota_m(a_n)\) are shown below.

For more information on an embedded modular form you can click on its label.

Copy content comment:embeddings in the coefficient field
 
Copy content gp:mfembed(f)
 
Label   \(\iota_m(\nu)\) \( a_{2} \) \( a_{3} \) \( a_{4} \) \( a_{5} \) \( a_{6} \) \( a_{7} \) \( a_{8} \) \( a_{9} \) \( a_{10} \)
629.1
1.93185i
0.517638i
1.93185i
0.517638i
1.41421i −1.73205 −2.00000 −1.73205 + 1.41421i 2.44949i 1.00000 2.44949i 2.82843i 3.00000 2.00000 + 2.44949i
629.2 1.41421i 1.73205 −2.00000 1.73205 + 1.41421i 2.44949i 1.00000 + 2.44949i 2.82843i 3.00000 2.00000 2.44949i
629.3 1.41421i −1.73205 −2.00000 −1.73205 1.41421i 2.44949i 1.00000 + 2.44949i 2.82843i 3.00000 2.00000 2.44949i
629.4 1.41421i 1.73205 −2.00000 1.73205 1.41421i 2.44949i 1.00000 2.44949i 2.82843i 3.00000 2.00000 + 2.44949i
\(n\): e.g. 2-40 or 990-1000
Significant digits:
Format:

Inner twists

Char Parity Ord Mult Type
1.a even 1 1 trivial
24.h odd 2 1 CM by \(\Q(\sqrt{-6}) \)
3.b odd 2 1 inner
8.b even 2 1 inner
35.c odd 2 1 inner
105.g even 2 1 inner
280.c odd 2 1 inner
840.u even 2 1 inner

Twists

       By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 840.2.u.b yes 4
3.b odd 2 1 inner 840.2.u.b yes 4
5.b even 2 1 840.2.u.a 4
7.b odd 2 1 840.2.u.a 4
8.b even 2 1 inner 840.2.u.b yes 4
15.d odd 2 1 840.2.u.a 4
21.c even 2 1 840.2.u.a 4
24.h odd 2 1 CM 840.2.u.b yes 4
35.c odd 2 1 inner 840.2.u.b yes 4
40.f even 2 1 840.2.u.a 4
56.h odd 2 1 840.2.u.a 4
105.g even 2 1 inner 840.2.u.b yes 4
120.i odd 2 1 840.2.u.a 4
168.i even 2 1 840.2.u.a 4
280.c odd 2 1 inner 840.2.u.b yes 4
840.u even 2 1 inner 840.2.u.b yes 4
    
        By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
840.2.u.a 4 5.b even 2 1
840.2.u.a 4 7.b odd 2 1
840.2.u.a 4 15.d odd 2 1
840.2.u.a 4 21.c even 2 1
840.2.u.a 4 40.f even 2 1
840.2.u.a 4 56.h odd 2 1
840.2.u.a 4 120.i odd 2 1
840.2.u.a 4 168.i even 2 1
840.2.u.b yes 4 1.a even 1 1 trivial
840.2.u.b yes 4 3.b odd 2 1 inner
840.2.u.b yes 4 8.b even 2 1 inner
840.2.u.b yes 4 24.h odd 2 1 CM
840.2.u.b yes 4 35.c odd 2 1 inner
840.2.u.b yes 4 105.g even 2 1 inner
840.2.u.b yes 4 280.c odd 2 1 inner
840.2.u.b yes 4 840.u even 2 1 inner

Hecke kernels

This newform subspace can be constructed as the intersection of the kernels of the following linear operators acting on \(S_{2}^{\mathrm{new}}(840, [\chi])\):

\( T_{11}^{2} - 12 \) Copy content Toggle raw display
\( T_{23} \) Copy content Toggle raw display
\( T_{73} + 14 \) Copy content Toggle raw display

Hecke characteristic polynomials

$p$ $F_p(T)$
$2$ \( (T^{2} + 2)^{2} \) Copy content Toggle raw display
$3$ \( (T^{2} - 3)^{2} \) Copy content Toggle raw display
$5$ \( T^{4} - 2T^{2} + 25 \) Copy content Toggle raw display
$7$ \( (T^{2} - 2 T + 7)^{2} \) Copy content Toggle raw display
$11$ \( (T^{2} - 12)^{2} \) Copy content Toggle raw display
$13$ \( T^{4} \) Copy content Toggle raw display
$17$ \( T^{4} \) Copy content Toggle raw display
$19$ \( T^{4} \) Copy content Toggle raw display
$23$ \( T^{4} \) Copy content Toggle raw display
$29$ \( (T^{2} - 108)^{2} \) Copy content Toggle raw display
$31$ \( (T^{2} + 24)^{2} \) Copy content Toggle raw display
$37$ \( T^{4} \) Copy content Toggle raw display
$41$ \( T^{4} \) Copy content Toggle raw display
$43$ \( T^{4} \) Copy content Toggle raw display
$47$ \( T^{4} \) Copy content Toggle raw display
$53$ \( (T^{2} + 200)^{2} \) Copy content Toggle raw display
$59$ \( (T^{2} + 128)^{2} \) Copy content Toggle raw display
$61$ \( T^{4} \) Copy content Toggle raw display
$67$ \( T^{4} \) Copy content Toggle raw display
$71$ \( T^{4} \) Copy content Toggle raw display
$73$ \( (T + 14)^{4} \) Copy content Toggle raw display
$79$ \( (T - 10)^{4} \) Copy content Toggle raw display
$83$ \( (T^{2} - 300)^{2} \) Copy content Toggle raw display
$89$ \( T^{4} \) Copy content Toggle raw display
$97$ \( (T - 2)^{4} \) Copy content Toggle raw display
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