Properties

Label 728.2.k.a
Level $728$
Weight $2$
Character orbit 728.k
Analytic conductor $5.813$
Analytic rank $0$
Dimension $8$
Inner twists $2$

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Newspace parameters

Copy content comment:Compute space of new eigenforms
 
Copy content gp:[N,k,chi] = [728,2,Mod(337,728)] mf = mfinit([N,k,chi],0) lf = mfeigenbasis(mf)
 
Copy content sage:from sage.modular.dirichlet import DirichletCharacter H = DirichletGroup(728, base_ring=CyclotomicField(2)) chi = DirichletCharacter(H, H._module([0, 0, 0, 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("728.337"); S:= CuspForms(chi, 2); N := Newforms(S);
 
Level: \( N \) \(=\) \( 728 = 2^{3} \cdot 7 \cdot 13 \)
Weight: \( k \) \(=\) \( 2 \)
Character orbit: \([\chi]\) \(=\) 728.k (of order \(2\), degree \(1\), minimal)

Newform invariants

Copy content comment:select newform
 
Copy content sage:traces = [8] 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: \(5.81310926715\)
Analytic rank: \(0\)
Dimension: \(8\)
Coefficient field: \(\mathbb{Q}[x]/(x^{8} + \cdots)\)
Copy content comment:defining polynomial
 
Copy content gp:f.mod \\ as an extension of the character field
 
Defining polynomial: \( x^{8} + 17x^{6} + 72x^{4} + 36x^{2} + 4 \) Copy content Toggle raw display
Coefficient ring: \(\Z[a_1, \ldots, a_{7}]\)
Coefficient ring index: \( 2 \)
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 \(1,\beta_1,\ldots,\beta_{7}\) for the coefficient ring described below. We also show the integral \(q\)-expansion of the trace form.

\(f(q)\) \(=\) \( q + \beta_{2} q^{3} + (\beta_{5} - \beta_1) q^{5} - \beta_{5} q^{7} + ( - \beta_{3} - \beta_{2} + 1) q^{9} + (\beta_{5} - \beta_{4}) q^{11} + ( - \beta_{4} - \beta_{2}) q^{13} + ( - \beta_{7} - 4 \beta_{5} + 2 \beta_1) q^{15}+ \cdots + (\beta_{7} + 2 \beta_{4} - 6 \beta_1) q^{99}+O(q^{100}) \) Copy content Toggle raw display
\(\operatorname{Tr}(f)(q)\) \(=\) \( 8 q - 2 q^{3} + 10 q^{9} + 2 q^{13} + 4 q^{17} + 20 q^{23} - 6 q^{25} - 26 q^{27} - 6 q^{29} + 10 q^{35} - 34 q^{39} - 14 q^{43} - 8 q^{49} + 20 q^{51} - 26 q^{53} - 24 q^{55} - 46 q^{61} - 14 q^{65} - 22 q^{69}+ \cdots - 34 q^{95}+O(q^{100}) \) Copy content Toggle raw display

Basis of coefficient ring in terms of a root \(\nu\) of \( x^{8} + 17x^{6} + 72x^{4} + 36x^{2} + 4 \) : Copy content Toggle raw display

\(\beta_{1}\)\(=\) \( \nu \) Copy content Toggle raw display
\(\beta_{2}\)\(=\) \( ( \nu^{6} + 15\nu^{4} + 52\nu^{2} + 12 ) / 10 \) Copy content Toggle raw display
\(\beta_{3}\)\(=\) \( ( -\nu^{6} - 15\nu^{4} - 42\nu^{2} + 28 ) / 10 \) Copy content Toggle raw display
\(\beta_{4}\)\(=\) \( ( -2\nu^{7} - 35\nu^{5} - 159\nu^{3} - 114\nu ) / 10 \) Copy content Toggle raw display
\(\beta_{5}\)\(=\) \( ( 3\nu^{7} + 50\nu^{5} + 201\nu^{3} + 56\nu ) / 10 \) Copy content Toggle raw display
\(\beta_{6}\)\(=\) \( ( -\nu^{6} - 17\nu^{4} - 70\nu^{2} - 18 ) / 2 \) Copy content Toggle raw display
\(\beta_{7}\)\(=\) \( ( -11\nu^{7} - 185\nu^{5} - 752\nu^{3} - 202\nu ) / 10 \) Copy content Toggle raw display
\(\nu\)\(=\) \( \beta_1 \) Copy content Toggle raw display
\(\nu^{2}\)\(=\) \( \beta_{3} + \beta_{2} - 4 \) Copy content Toggle raw display
\(\nu^{3}\)\(=\) \( \beta_{7} + 3\beta_{5} - \beta_{4} - 8\beta_1 \) Copy content Toggle raw display
\(\nu^{4}\)\(=\) \( -\beta_{6} - 9\beta_{3} - 14\beta_{2} + 33 \) Copy content Toggle raw display
\(\nu^{5}\)\(=\) \( -15\beta_{7} - 49\beta_{5} + 9\beta_{4} + 74\beta_1 \) Copy content Toggle raw display
\(\nu^{6}\)\(=\) \( 15\beta_{6} + 83\beta_{3} + 168\beta_{2} - 299 \) Copy content Toggle raw display
\(\nu^{7}\)\(=\) \( 183\beta_{7} + 619\beta_{5} - 83\beta_{4} - 716\beta_1 \) Copy content Toggle raw display

Character values

We give the values of \(\chi\) on generators for \(\left(\mathbb{Z}/728\mathbb{Z}\right)^\times\).

\(n\) \(183\) \(365\) \(521\) \(561\)
\(\chi(n)\) \(1\) \(1\) \(1\) \(-1\)

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   \(\iota_m(\nu)\) \( a_{2} \) \( a_{3} \) \( a_{4} \) \( a_{5} \) \( a_{6} \) \( a_{7} \) \( a_{8} \) \( a_{9} \) \( a_{10} \)
337.1
3.22732i
3.22732i
0.629066i
0.629066i
0.401251i
0.401251i
2.45513i
2.45513i
0 −3.22732 0 4.22732i 0 1.00000i 0 7.41559 0
337.2 0 −3.22732 0 4.22732i 0 1.00000i 0 7.41559 0
337.3 0 −0.629066 0 1.62907i 0 1.00000i 0 −2.60428 0
337.4 0 −0.629066 0 1.62907i 0 1.00000i 0 −2.60428 0
337.5 0 0.401251 0 0.598749i 0 1.00000i 0 −2.83900 0
337.6 0 0.401251 0 0.598749i 0 1.00000i 0 −2.83900 0
337.7 0 2.45513 0 1.45513i 0 1.00000i 0 3.02768 0
337.8 0 2.45513 0 1.45513i 0 1.00000i 0 3.02768 0
\(n\): e.g. 2-40 or 990-1000
Embeddings: e.g. 1-3 or 337.8
Significant digits:
Format:

Inner twists

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

Twists

       By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 728.2.k.a 8
4.b odd 2 1 1456.2.k.e 8
13.b even 2 1 inner 728.2.k.a 8
13.d odd 4 1 9464.2.a.x 4
13.d odd 4 1 9464.2.a.y 4
52.b odd 2 1 1456.2.k.e 8
    
        By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
728.2.k.a 8 1.a even 1 1 trivial
728.2.k.a 8 13.b even 2 1 inner
1456.2.k.e 8 4.b odd 2 1
1456.2.k.e 8 52.b odd 2 1
9464.2.a.x 4 13.d odd 4 1
9464.2.a.y 4 13.d odd 4 1

Hecke kernels

This newform subspace can be constructed as the kernel of the linear operator \( T_{3}^{4} + T_{3}^{3} - 8T_{3}^{2} - 2T_{3} + 2 \) acting on \(S_{2}^{\mathrm{new}}(728, [\chi])\). Copy content Toggle raw display

Hecke characteristic polynomials

$p$ $F_p(T)$
$2$ \( T^{8} \) Copy content Toggle raw display
$3$ \( (T^{4} + T^{3} - 8 T^{2} + \cdots + 2)^{2} \) Copy content Toggle raw display
$5$ \( T^{8} + 23 T^{6} + \cdots + 36 \) Copy content Toggle raw display
$7$ \( (T^{2} + 1)^{4} \) Copy content Toggle raw display
$11$ \( T^{8} + 37 T^{6} + \cdots + 2500 \) Copy content Toggle raw display
$13$ \( T^{8} - 2 T^{7} + \cdots + 28561 \) Copy content Toggle raw display
$17$ \( (T^{4} - 2 T^{3} + \cdots - 156)^{2} \) Copy content Toggle raw display
$19$ \( T^{8} + 47 T^{6} + \cdots + 400 \) Copy content Toggle raw display
$23$ \( (T^{4} - 10 T^{3} + \cdots - 97)^{2} \) Copy content Toggle raw display
$29$ \( (T^{4} + 3 T^{3} - 61 T^{2} + \cdots - 80)^{2} \) Copy content Toggle raw display
$31$ \( T^{8} + 92 T^{6} + \cdots + 961 \) Copy content Toggle raw display
$37$ \( T^{8} + 69 T^{6} + \cdots + 66564 \) Copy content Toggle raw display
$41$ \( T^{8} + 93 T^{6} + \cdots + 576 \) Copy content Toggle raw display
$43$ \( (T^{4} + 7 T^{3} - 33 T^{2} + \cdots - 52)^{2} \) Copy content Toggle raw display
$47$ \( T^{8} + 128 T^{6} + \cdots + 1521 \) Copy content Toggle raw display
$53$ \( (T^{4} + 13 T^{3} + \cdots + 186)^{2} \) Copy content Toggle raw display
$59$ \( T^{8} + 168 T^{6} + \cdots + 576 \) Copy content Toggle raw display
$61$ \( (T^{4} + 23 T^{3} + \cdots - 1480)^{2} \) Copy content Toggle raw display
$67$ \( T^{8} + 185 T^{6} + \cdots + 186624 \) Copy content Toggle raw display
$71$ \( T^{8} + 128 T^{6} + \cdots + 331776 \) Copy content Toggle raw display
$73$ \( T^{8} + 96 T^{6} + \cdots + 169 \) Copy content Toggle raw display
$79$ \( (T^{4} + 20 T^{3} + \cdots + 729)^{2} \) Copy content Toggle raw display
$83$ \( T^{8} + 415 T^{6} + \cdots + 3048516 \) Copy content Toggle raw display
$89$ \( T^{8} + 315 T^{6} + \cdots + 10562500 \) Copy content Toggle raw display
$97$ \( T^{8} + 632 T^{6} + \cdots + 226051225 \) Copy content Toggle raw display
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