Properties

Label 28.7.b.a
Level $28$
Weight $7$
Character orbit 28.b
Analytic conductor $6.442$
Analytic rank $0$
Dimension $4$
CM no
Inner twists $2$

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Newspace parameters

comment: Compute space of new eigenforms
 
[N,k,chi] = [28,7,Mod(13,28)]
 
mf = mfinit([N,k,chi],0)
 
lf = mfeigenbasis(mf)
 
from sage.modular.dirichlet import DirichletCharacter
 
H = DirichletGroup(28, base_ring=CyclotomicField(2))
 
chi = DirichletCharacter(H, H._module([0, 1]))
 
N = Newforms(chi, 7, names="a")
 
//Please install CHIMP (https://github.com/edgarcosta/CHIMP) if you want to run this code
 
chi := DirichletCharacter("28.13");
 
S:= CuspForms(chi, 7);
 
N := Newforms(S);
 
Level: \( N \) \(=\) \( 28 = 2^{2} \cdot 7 \)
Weight: \( k \) \(=\) \( 7 \)
Character orbit: \([\chi]\) \(=\) 28.b (of order \(2\), degree \(1\), minimal)

Newform invariants

comment: select newform
 
sage: f = N[0] # Warning: the index may be different
 
gp: f = lf[1] \\ Warning: the index may be different
 
Self dual: no
Analytic conductor: \(6.44151434136\)
Analytic rank: \(0\)
Dimension: \(4\)
Coefficient field: 4.0.903168.1
comment: defining polynomial
 
gp: f.mod \\ as an extension of the character field
 
Defining polynomial: \( x^{4} + 24x^{2} + 18 \) Copy content Toggle raw display
Coefficient ring: \(\Z[a_1, \ldots, a_{7}]\)
Coefficient ring index: \( 2^{7}\cdot 3\cdot 7^{2} \)
Twist minimal: yes
Sato-Tate group: $\mathrm{SU}(2)[C_{2}]$

$q$-expansion

comment: q-expansion
 
sage: f.q_expansion() # note that sage often uses an isomorphic number field
 
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.

\(f(q)\) \(=\) \( q - \beta_{2} q^{3} + \beta_1 q^{5} + ( - \beta_{3} + 2 \beta_{2} - \beta_1 - 7) q^{7} + ( - 2 \beta_{3} - 39) q^{9}+O(q^{10}) \) Copy content Toggle raw display \( q - \beta_{2} q^{3} + \beta_1 q^{5} + ( - \beta_{3} + 2 \beta_{2} - \beta_1 - 7) q^{7} + ( - 2 \beta_{3} - 39) q^{9} + ( - 4 \beta_{3} - 54) q^{11} + ( - 26 \beta_{2} + 25 \beta_1) q^{13} + ( - 6 \beta_{3} + 192) q^{15} + ( - 210 \beta_{2} - 26 \beta_1) q^{17} + (221 \beta_{2} + 14 \beta_1) q^{19} + (10 \beta_{3} + 274 \beta_{2} + \cdots + 1344) q^{21}+ \cdots + (264 \beta_{3} + 792378) q^{99}+O(q^{100}) \) Copy content Toggle raw display
\(\operatorname{Tr}(f)(q)\) \(=\) \( 4 q - 28 q^{7} - 156 q^{9}+O(q^{10}) \) Copy content Toggle raw display \( 4 q - 28 q^{7} - 156 q^{9} - 216 q^{11} + 768 q^{15} + 5376 q^{21} - 13752 q^{23} - 3548 q^{25} + 34920 q^{29} + 64512 q^{35} - 158936 q^{37} - 60672 q^{39} + 215080 q^{43} + 320068 q^{49} - 665088 q^{51} - 158040 q^{53} + 689664 q^{57} + 791364 q^{63} - 1631232 q^{65} - 511000 q^{67} + 1648584 q^{71} + 1582056 q^{77} - 2827768 q^{79} - 652860 q^{81} + 1878528 q^{85} + 1752576 q^{91} - 3838464 q^{93} - 1094400 q^{95} + 3169512 q^{99}+O(q^{100}) \) Copy content Toggle raw display

Basis of coefficient ring in terms of a root \(\nu\) of \( x^{4} + 24x^{2} + 18 \) : Copy content Toggle raw display

\(\beta_{1}\)\(=\) \( ( 2\nu^{3} + 156\nu ) / 3 \) Copy content Toggle raw display
\(\beta_{2}\)\(=\) \( -2\nu^{3} - 44\nu \) Copy content Toggle raw display
\(\beta_{3}\)\(=\) \( 28\nu^{2} + 336 \) Copy content Toggle raw display
\(\nu\)\(=\) \( ( \beta_{2} + 3\beta_1 ) / 112 \) Copy content Toggle raw display
\(\nu^{2}\)\(=\) \( ( \beta_{3} - 336 ) / 28 \) Copy content Toggle raw display
\(\nu^{3}\)\(=\) \( ( -39\beta_{2} - 33\beta_1 ) / 56 \) Copy content Toggle raw display

Character values

We give the values of \(\chi\) on generators for \(\left(\mathbb{Z}/28\mathbb{Z}\right)^\times\).

\(n\) \(15\) \(17\)
\(\chi(n)\) \(1\) \(-1\)

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.

comment: embeddings in the coefficient field
 
gp: mfembed(f)
 
Label   \(\iota_m(\nu)\) \( a_{2} \) \( a_{3} \) \( a_{4} \) \( a_{5} \) \( a_{6} \) \( a_{7} \) \( a_{8} \) \( a_{9} \) \( a_{10} \)
13.1
0.880357i
4.81923i
4.81923i
0.880357i
0 37.3711i 0 45.3237i 0 −321.299 + 120.066i 0 −667.598 0
13.2 0 11.8068i 0 175.982i 0 307.299 152.369i 0 589.598 0
13.3 0 11.8068i 0 175.982i 0 307.299 + 152.369i 0 589.598 0
13.4 0 37.3711i 0 45.3237i 0 −321.299 120.066i 0 −667.598 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
7.b odd 2 1 inner

Twists

       By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 28.7.b.a 4
3.b odd 2 1 252.7.d.a 4
4.b odd 2 1 112.7.c.d 4
5.b even 2 1 700.7.d.b 4
5.c odd 4 2 700.7.h.a 8
7.b odd 2 1 inner 28.7.b.a 4
7.c even 3 2 196.7.h.b 8
7.d odd 6 2 196.7.h.b 8
8.b even 2 1 448.7.c.f 4
8.d odd 2 1 448.7.c.g 4
21.c even 2 1 252.7.d.a 4
28.d even 2 1 112.7.c.d 4
35.c odd 2 1 700.7.d.b 4
35.f even 4 2 700.7.h.a 8
56.e even 2 1 448.7.c.g 4
56.h odd 2 1 448.7.c.f 4
    
        By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
28.7.b.a 4 1.a even 1 1 trivial
28.7.b.a 4 7.b odd 2 1 inner
112.7.c.d 4 4.b odd 2 1
112.7.c.d 4 28.d even 2 1
196.7.h.b 8 7.c even 3 2
196.7.h.b 8 7.d odd 6 2
252.7.d.a 4 3.b odd 2 1
252.7.d.a 4 21.c even 2 1
448.7.c.f 4 8.b even 2 1
448.7.c.f 4 56.h odd 2 1
448.7.c.g 4 8.d odd 2 1
448.7.c.g 4 56.e even 2 1
700.7.d.b 4 5.b even 2 1
700.7.d.b 4 35.c odd 2 1
700.7.h.a 8 5.c odd 4 2
700.7.h.a 8 35.f even 4 2

Hecke kernels

This newform subspace is the entire newspace \(S_{7}^{\mathrm{new}}(28, [\chi])\).

Hecke characteristic polynomials

$p$ $F_p(T)$
$2$ \( T^{4} \) Copy content Toggle raw display
$3$ \( T^{4} + 1536 T^{2} + 194688 \) Copy content Toggle raw display
$5$ \( T^{4} + 33024 T^{2} + 63619200 \) Copy content Toggle raw display
$7$ \( T^{4} + \cdots + 13841287201 \) Copy content Toggle raw display
$11$ \( (T^{2} + 108 T - 1577628)^{2} \) Copy content Toggle raw display
$13$ \( T^{4} + \cdots + 74197833257088 \) Copy content Toggle raw display
$17$ \( T^{4} + \cdots + 22\!\cdots\!00 \) Copy content Toggle raw display
$19$ \( T^{4} + \cdots + 14\!\cdots\!00 \) Copy content Toggle raw display
$23$ \( (T^{2} + 6876 T - 13468860)^{2} \) Copy content Toggle raw display
$29$ \( (T^{2} - 17460 T - 380564316)^{2} \) Copy content Toggle raw display
$31$ \( T^{4} + \cdots + 28\!\cdots\!00 \) Copy content Toggle raw display
$37$ \( (T^{2} + 79468 T + 1564565860)^{2} \) Copy content Toggle raw display
$41$ \( T^{4} + \cdots + 84\!\cdots\!00 \) Copy content Toggle raw display
$43$ \( (T^{2} - 107540 T - 4853452700)^{2} \) Copy content Toggle raw display
$47$ \( T^{4} + \cdots + 91\!\cdots\!72 \) Copy content Toggle raw display
$53$ \( (T^{2} + 79020 T - 11241366300)^{2} \) Copy content Toggle raw display
$59$ \( T^{4} + \cdots + 12\!\cdots\!00 \) Copy content Toggle raw display
$61$ \( T^{4} + \cdots + 29\!\cdots\!00 \) Copy content Toggle raw display
$67$ \( (T^{2} + 255500 T + 15687844900)^{2} \) Copy content Toggle raw display
$71$ \( (T^{2} - 824292 T + 115477411140)^{2} \) Copy content Toggle raw display
$73$ \( T^{4} + \cdots + 48\!\cdots\!52 \) Copy content Toggle raw display
$79$ \( (T^{2} + 1413884 T + 454357567108)^{2} \) Copy content Toggle raw display
$83$ \( T^{4} + \cdots + 83\!\cdots\!08 \) Copy content Toggle raw display
$89$ \( T^{4} + \cdots + 12\!\cdots\!00 \) Copy content Toggle raw display
$97$ \( T^{4} + \cdots + 73\!\cdots\!68 \) Copy content Toggle raw display
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