Properties

Label 656.4.d.b
Level $656$
Weight $4$
Character orbit 656.d
Analytic conductor $38.705$
Analytic rank $0$
Dimension $4$
Inner twists $2$

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Newspace parameters

Copy content comment:Compute space of new eigenforms
 
Copy content gp:[N,k,chi] = [656,4,Mod(81,656)] mf = mfinit([N,k,chi],0) lf = mfeigenbasis(mf)
 
Copy content magma://Please install CHIMP (https://github.com/edgarcosta/CHIMP) if you want to run this code chi := DirichletCharacter("656.81"); S:= CuspForms(chi, 4); N := Newforms(S);
 
Copy content sage:from sage.modular.dirichlet import DirichletCharacter H = DirichletGroup(656, base_ring=CyclotomicField(2)) chi = DirichletCharacter(H, H._module([0, 0, 1])) N = Newforms(chi, 4, names="a")
 
Level: \( N \) \(=\) \( 656 = 2^{4} \cdot 41 \)
Weight: \( k \) \(=\) \( 4 \)
Character orbit: \([\chi]\) \(=\) 656.d (of order \(2\), degree \(1\), not minimal)

Newform invariants

Copy content comment:select newform
 
Copy content sage:traces = [4,0,0,0,4] f = next(g for g in N if [g.coefficient(i+1).trace() for i in range(5)] == traces)
 
Copy content gp:f = lf[1] \\ Warning: the index may be different
 
Self dual: no
Analytic conductor: \(38.7052529638\)
Analytic rank: \(0\)
Dimension: \(4\)
Coefficient field: \(\Q(\sqrt{-10}, \sqrt{-66})\)
Copy content comment:defining polynomial
 
Copy content gp:f.mod \\ as an extension of the character field
 
Defining polynomial: \( x^{4} + 38x^{2} + 196 \) Copy content Toggle raw display
Coefficient ring: \(\Z[a_1, \ldots, a_{7}]\)
Coefficient ring index: \( 2^{2} \)
Twist minimal: no (minimal twist has level 82)
Sato-Tate group: $\mathrm{SU}(2)[C_{2}]$

$q$-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.

\(f(q)\) \(=\) \( q + \beta_1 q^{3} + ( - \beta_{3} + 1) q^{5} + ( - 2 \beta_{2} - \beta_1) q^{7} + (\beta_{3} + 8) q^{9} + ( - \beta_{2} + 6 \beta_1) q^{11} + (9 \beta_{2} - 5 \beta_1) q^{13} + ( - 7 \beta_{2} + 13 \beta_1) q^{15}+ \cdots + (22 \beta_{2} - 27 \beta_1) q^{99}+O(q^{100}) \) Copy content Toggle raw display
\(\operatorname{Tr}(f)(q)\) \(=\) \( 4 q + 4 q^{5} + 32 q^{9} + 148 q^{21} + 8 q^{23} + 164 q^{25} + 312 q^{31} - 420 q^{33} - 44 q^{37} + 56 q^{39} + 164 q^{41} - 552 q^{43} - 628 q^{45} + 528 q^{49} - 288 q^{51} - 28 q^{57} + 40 q^{59} - 32 q^{61}+ \cdots + 2392 q^{91}+O(q^{100}) \) Copy content Toggle raw display

Basis of coefficient ring in terms of a root \(\nu\) of \( x^{4} + 38x^{2} + 196 \) : Copy content Toggle raw display

\(\beta_{1}\)\(=\) \( \nu \) Copy content Toggle raw display
\(\beta_{2}\)\(=\) \( ( \nu^{3} + 31\nu ) / 7 \) Copy content Toggle raw display
\(\beta_{3}\)\(=\) \( \nu^{2} + 19 \) Copy content Toggle raw display
\(\nu\)\(=\) \( \beta_1 \) Copy content Toggle raw display
\(\nu^{2}\)\(=\) \( \beta_{3} - 19 \) Copy content Toggle raw display
\(\nu^{3}\)\(=\) \( 7\beta_{2} - 31\beta_1 \) Copy content Toggle raw display

Character values

We give the values of \(\chi\) on generators for \(\left(\mathbb{Z}/656\mathbb{Z}\right)^\times\).

\(n\) \(129\) \(165\) \(575\)
\(\chi(n)\) \(-1\) \(1\) \(1\)

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   \(\iota_m(\nu)\) \( a_{2} \) \( a_{3} \) \( a_{4} \) \( a_{5} \) \( a_{6} \) \( a_{7} \) \( a_{8} \) \( a_{9} \) \( a_{10} \)
81.1
5.64316i
2.48088i
2.48088i
5.64316i
0 5.64316i 0 13.8452 0 4.28036i 0 −4.84523 0
81.2 0 2.48088i 0 −11.8452 0 20.0918i 0 20.8452 0
81.3 0 2.48088i 0 −11.8452 0 20.0918i 0 20.8452 0
81.4 0 5.64316i 0 13.8452 0 4.28036i 0 −4.84523 0
\(n\): e.g. 2-40 or 990-1000
Significant digits:
Format:

Inner twists

Char Parity Ord Mult Type
1.a even 1 1 trivial
41.b even 2 1 inner

Twists

       By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 656.4.d.b 4
4.b odd 2 1 82.4.b.a 4
12.b even 2 1 738.4.d.a 4
41.b even 2 1 inner 656.4.d.b 4
164.d odd 2 1 82.4.b.a 4
492.d even 2 1 738.4.d.a 4
    
        By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
82.4.b.a 4 4.b odd 2 1
82.4.b.a 4 164.d odd 2 1
656.4.d.b 4 1.a even 1 1 trivial
656.4.d.b 4 41.b even 2 1 inner
738.4.d.a 4 12.b even 2 1
738.4.d.a 4 492.d even 2 1

Hecke kernels

This newform subspace can be constructed as the kernel of the linear operator \( T_{3}^{4} + 38T_{3}^{2} + 196 \) acting on \(S_{4}^{\mathrm{new}}(656, [\chi])\). Copy content Toggle raw display

Hecke characteristic polynomials

$p$ $F_p(T)$
$2$ \( T^{4} \) Copy content Toggle raw display
$3$ \( T^{4} + 38T^{2} + 196 \) Copy content Toggle raw display
$5$ \( (T^{2} - 2 T - 164)^{2} \) Copy content Toggle raw display
$7$ \( T^{4} + 422T^{2} + 7396 \) Copy content Toggle raw display
$11$ \( T^{4} + 1230 T^{2} + 44100 \) Copy content Toggle raw display
$13$ \( T^{4} + 5648 T^{2} + 5271616 \) Copy content Toggle raw display
$17$ \( T^{4} + 4992 T^{2} + 147456 \) Copy content Toggle raw display
$19$ \( T^{4} + 13622 T^{2} + 26977636 \) Copy content Toggle raw display
$23$ \( (T^{2} - 4 T - 656)^{2} \) Copy content Toggle raw display
$29$ \( T^{4} + 43472 T^{2} + 288456256 \) Copy content Toggle raw display
$31$ \( (T^{2} - 156 T + 5424)^{2} \) Copy content Toggle raw display
$37$ \( (T^{2} + 22 T - 72644)^{2} \) Copy content Toggle raw display
$41$ \( (T^{2} - 82 T + 68921)^{2} \) Copy content Toggle raw display
$43$ \( (T^{2} + 276 T - 34416)^{2} \) Copy content Toggle raw display
$47$ \( T^{4} + \cdots + 59353627876 \) Copy content Toggle raw display
$53$ \( T^{4} + 66768 T^{2} + 621804096 \) Copy content Toggle raw display
$59$ \( (T^{2} - 20 T - 290960)^{2} \) Copy content Toggle raw display
$61$ \( (T^{2} + 16 T - 190676)^{2} \) Copy content Toggle raw display
$67$ \( T^{4} + 869342 T^{2} + 291248356 \) Copy content Toggle raw display
$71$ \( T^{4} + \cdots + 255277562500 \) Copy content Toggle raw display
$73$ \( (T^{2} + 74 T - 877916)^{2} \) Copy content Toggle raw display
$79$ \( T^{4} + \cdots + 18590231716 \) Copy content Toggle raw display
$83$ \( (T^{2} - 744 T - 379056)^{2} \) Copy content Toggle raw display
$89$ \( T^{4} + \cdots + 801497629696 \) Copy content Toggle raw display
$97$ \( T^{4} + \cdots + 29342319616 \) Copy content Toggle raw display
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