Properties

Label 228.2.d.b
Level $228$
Weight $2$
Character orbit 228.d
Analytic conductor $1.821$
Analytic rank $0$
Dimension $4$
Inner twists $4$

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Newspace parameters

Copy content comment:Compute space of new eigenforms
 
Copy content gp:[N,k,chi] = [228,2,Mod(113,228)] mf = mfinit([N,k,chi],0) lf = mfeigenbasis(mf)
 
Copy content sage:from sage.modular.dirichlet import DirichletCharacter H = DirichletGroup(228, base_ring=CyclotomicField(2)) chi = DirichletCharacter(H, H._module([0, 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("228.113"); S:= CuspForms(chi, 2); N := Newforms(S);
 
Level: \( N \) \(=\) \( 228 = 2^{2} \cdot 3 \cdot 19 \)
Weight: \( k \) \(=\) \( 2 \)
Character orbit: \([\chi]\) \(=\) 228.d (of order \(2\), degree \(1\), minimal)

Newform invariants

Copy content comment:select newform
 
Copy content sage:traces = [4] f = next(g for g in N if [g.coefficient(i+1).trace() for i in range(1)] == traces)
 
Copy content gp:f = lf[1] \\ Warning: the index may be different
 
Self dual: no
Analytic conductor: \(1.82058916609\)
Analytic rank: \(0\)
Dimension: \(4\)
Coefficient field: \(\Q(\sqrt{-2}, \sqrt{-5})\)
Copy content comment:defining polynomial
 
Copy content gp:f.mod \\ as an extension of the character field
 
Defining polynomial: \( x^{4} - 4x^{2} + 9 \) Copy content Toggle raw display
Coefficient ring: \(\Z[a_1, a_2, a_3]\)
Coefficient ring index: \( 3 \)
Twist minimal: yes
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.

\(f(q)\) \(=\) \( q + \beta_1 q^{3} + \beta_{2} q^{5} - q^{7} + (\beta_{2} + 2) q^{9} + \beta_{2} q^{11} + ( - \beta_{3} - \beta_1) q^{13} + \beta_{3} q^{15} + \beta_{2} q^{17} + ( - \beta_{3} - \beta_1 + 1) q^{19} - \beta_1 q^{21}+ \cdots + (2 \beta_{2} - 5) q^{99}+O(q^{100}) \) Copy content Toggle raw display
\(\operatorname{Tr}(f)(q)\) \(=\) \( 4 q - 4 q^{7} + 8 q^{9} + 4 q^{19} + 12 q^{39} - 28 q^{43} - 20 q^{45} - 24 q^{49} - 20 q^{55} + 12 q^{57} + 44 q^{61} - 8 q^{63} + 20 q^{73} - 4 q^{81} - 20 q^{85} + 12 q^{93} - 20 q^{99}+O(q^{100}) \) Copy content Toggle raw display

Basis of coefficient ring in terms of a root \(\nu\) of \( x^{4} - 4x^{2} + 9 \) : Copy content Toggle raw display

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

Character values

We give the values of \(\chi\) on generators for \(\left(\mathbb{Z}/228\mathbb{Z}\right)^\times\).

\(n\) \(77\) \(97\) \(115\)
\(\chi(n)\) \(-1\) \(-1\) \(1\)

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   \(\iota_m(\nu)\) \( a_{2} \) \( a_{3} \) \( a_{4} \) \( a_{5} \) \( a_{6} \) \( a_{7} \) \( a_{8} \) \( a_{9} \) \( a_{10} \)
113.1
−1.58114 0.707107i
−1.58114 + 0.707107i
1.58114 0.707107i
1.58114 + 0.707107i
0 −1.58114 0.707107i 0 2.23607i 0 −1.00000 0 2.00000 + 2.23607i 0
113.2 0 −1.58114 + 0.707107i 0 2.23607i 0 −1.00000 0 2.00000 2.23607i 0
113.3 0 1.58114 0.707107i 0 2.23607i 0 −1.00000 0 2.00000 2.23607i 0
113.4 0 1.58114 + 0.707107i 0 2.23607i 0 −1.00000 0 2.00000 + 2.23607i 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
3.b odd 2 1 inner
19.b odd 2 1 inner
57.d even 2 1 inner

Twists

       By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 228.2.d.b 4
3.b odd 2 1 inner 228.2.d.b 4
4.b odd 2 1 912.2.f.g 4
12.b even 2 1 912.2.f.g 4
19.b odd 2 1 inner 228.2.d.b 4
57.d even 2 1 inner 228.2.d.b 4
76.d even 2 1 912.2.f.g 4
228.b odd 2 1 912.2.f.g 4
    
        By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
228.2.d.b 4 1.a even 1 1 trivial
228.2.d.b 4 3.b odd 2 1 inner
228.2.d.b 4 19.b odd 2 1 inner
228.2.d.b 4 57.d even 2 1 inner
912.2.f.g 4 4.b odd 2 1
912.2.f.g 4 12.b even 2 1
912.2.f.g 4 76.d even 2 1
912.2.f.g 4 228.b odd 2 1

Hecke kernels

This newform subspace can be constructed as the kernel of the linear operator \( T_{5}^{2} + 5 \) acting on \(S_{2}^{\mathrm{new}}(228, [\chi])\). Copy content Toggle raw display

Hecke characteristic polynomials

$p$ $F_p(T)$
$2$ \( T^{4} \) Copy content Toggle raw display
$3$ \( T^{4} - 4T^{2} + 9 \) Copy content Toggle raw display
$5$ \( (T^{2} + 5)^{2} \) Copy content Toggle raw display
$7$ \( (T + 1)^{4} \) Copy content Toggle raw display
$11$ \( (T^{2} + 5)^{2} \) Copy content Toggle raw display
$13$ \( (T^{2} + 18)^{2} \) Copy content Toggle raw display
$17$ \( (T^{2} + 5)^{2} \) Copy content Toggle raw display
$19$ \( (T^{2} - 2 T + 19)^{2} \) Copy content Toggle raw display
$23$ \( (T^{2} + 20)^{2} \) Copy content Toggle raw display
$29$ \( T^{4} \) Copy content Toggle raw display
$31$ \( (T^{2} + 18)^{2} \) Copy content Toggle raw display
$37$ \( (T^{2} + 18)^{2} \) Copy content Toggle raw display
$41$ \( (T^{2} - 90)^{2} \) Copy content Toggle raw display
$43$ \( (T + 7)^{4} \) Copy content Toggle raw display
$47$ \( (T^{2} + 125)^{2} \) Copy content Toggle raw display
$53$ \( (T^{2} - 90)^{2} \) Copy content Toggle raw display
$59$ \( (T^{2} - 90)^{2} \) Copy content Toggle raw display
$61$ \( (T - 11)^{4} \) Copy content Toggle raw display
$67$ \( (T^{2} + 72)^{2} \) Copy content Toggle raw display
$71$ \( (T^{2} - 90)^{2} \) Copy content Toggle raw display
$73$ \( (T - 5)^{4} \) Copy content Toggle raw display
$79$ \( T^{4} \) Copy content Toggle raw display
$83$ \( (T^{2} + 80)^{2} \) Copy content Toggle raw display
$89$ \( (T^{2} - 90)^{2} \) Copy content Toggle raw display
$97$ \( (T^{2} + 162)^{2} \) Copy content Toggle raw display
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