Properties

Label 21.8.e.b
Level $21$
Weight $8$
Character orbit 21.e
Analytic conductor $6.560$
Analytic rank $0$
Dimension $10$
Inner twists $2$

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Newspace parameters

Copy content comment:Compute space of new eigenforms
 
Copy content gp:[N,k,chi] = [21,8,Mod(4,21)] 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("21.4"); S:= CuspForms(chi, 8); N := Newforms(S);
 
Copy content sage:from sage.modular.dirichlet import DirichletCharacter H = DirichletGroup(21, base_ring=CyclotomicField(6)) chi = DirichletCharacter(H, H._module([0, 4])) N = Newforms(chi, 8, names="a")
 
Level: \( N \) \(=\) \( 21 = 3 \cdot 7 \)
Weight: \( k \) \(=\) \( 8 \)
Character orbit: \([\chi]\) \(=\) 21.e (of order \(3\), degree \(2\), minimal)

Newform invariants

Copy content comment:select newform
 
Copy content sage:traces = [10] 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: \(6.56008553517\)
Analytic rank: \(0\)
Dimension: \(10\)
Relative dimension: \(5\) over \(\Q(\zeta_{3})\)
Coefficient field: \(\mathbb{Q}[x]/(x^{10} + \cdots)\)
Copy content comment:defining polynomial
 
Copy content gp:f.mod \\ as an extension of the character field
 
Defining polynomial: \( x^{10} + 412 x^{8} - 96 x^{7} + 133333 x^{6} - 66144 x^{5} + 15003636 x^{4} - 36459504 x^{3} + \cdots + 2149991424 \) Copy content Toggle raw display
Coefficient ring: \(\Z[a_1, \ldots, a_{7}]\)
Coefficient ring index: \( 2^{2}\cdot 3^{3}\cdot 7^{3} \)
Twist minimal: yes
Sato-Tate group: $\mathrm{SU}(2)[C_{3}]$

$q$-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 \(1,\beta_1,\ldots,\beta_{9}\) for the coefficient ring described below. We also show the integral \(q\)-expansion of the trace form.

\(f(q)\) \(=\) \( q + (3 \beta_{4} - \beta_1 - 3) q^{2} + 27 \beta_{4} q^{3} + (\beta_{8} - 46 \beta_{4} + \cdots + 6 \beta_1) q^{4} + ( - \beta_{9} + \beta_{8} + \beta_{5} + \cdots + 40) q^{5} + (27 \beta_{2} - 81) q^{6}+ \cdots + ( - 1458 \beta_{8} - 1458 \beta_{7} + \cdots + 1059966) q^{99}+O(q^{100}) \) Copy content Toggle raw display
\(\operatorname{Tr}(f)(q)\) \(=\) \( 10 q - 15 q^{2} + 135 q^{3} - 229 q^{4} + 198 q^{5} - 810 q^{6} - 859 q^{7} + 7134 q^{8} - 3645 q^{9} + 5081 q^{10} - 7248 q^{11} + 6183 q^{12} - 2546 q^{13} - 54 q^{14} + 10692 q^{15} + 14759 q^{16} + 34764 q^{17}+ \cdots + 10567584 q^{99}+O(q^{100}) \) Copy content Toggle raw display

Basis of coefficient ring in terms of a root \(\nu\) of \( x^{10} + 412 x^{8} - 96 x^{7} + 133333 x^{6} - 66144 x^{5} + 15003636 x^{4} - 36459504 x^{3} + \cdots + 2149991424 \) : Copy content Toggle raw display

\(\beta_{1}\)\(=\) \( \nu \) Copy content Toggle raw display
\(\beta_{2}\)\(=\) \( ( - 19608482386725 \nu^{9} + 25091781738784 \nu^{8} + 18325249512448 \nu^{7} + \cdots - 12\!\cdots\!68 ) / 95\!\cdots\!47 \) Copy content Toggle raw display
\(\beta_{3}\)\(=\) \( ( - 25091781738784 \nu^{9} + \cdots - 15\!\cdots\!55 ) / 95\!\cdots\!47 \) Copy content Toggle raw display
\(\beta_{4}\)\(=\) \( ( - 37\!\cdots\!43 \nu^{9} + \cdots + 63\!\cdots\!20 ) / 63\!\cdots\!28 \) Copy content Toggle raw display
\(\beta_{5}\)\(=\) \( ( 470544062002577 \nu^{9} + \cdots + 14\!\cdots\!40 ) / 38\!\cdots\!88 \) Copy content Toggle raw display
\(\beta_{6}\)\(=\) \( ( 51\!\cdots\!30 \nu^{9} + \cdots - 42\!\cdots\!48 ) / 37\!\cdots\!96 \) Copy content Toggle raw display
\(\beta_{7}\)\(=\) \( ( 44\!\cdots\!17 \nu^{9} + \cdots - 18\!\cdots\!64 ) / 21\!\cdots\!76 \) Copy content Toggle raw display
\(\beta_{8}\)\(=\) \( ( - 20\!\cdots\!65 \nu^{9} + \cdots + 34\!\cdots\!00 ) / 21\!\cdots\!76 \) Copy content Toggle raw display
\(\beta_{9}\)\(=\) \( ( - 71\!\cdots\!41 \nu^{9} + \cdots + 11\!\cdots\!88 ) / 31\!\cdots\!64 \) Copy content Toggle raw display
\(\nu\)\(=\) \( \beta_1 \) Copy content Toggle raw display
\(\nu^{2}\)\(=\) \( \beta_{8} - 165\beta_{4} \) Copy content Toggle raw display
\(\nu^{3}\)\(=\) \( -\beta_{8} - \beta_{7} - 2\beta_{6} - \beta_{5} - 3\beta_{3} + 236\beta_{2} + 29 \) Copy content Toggle raw display
\(\nu^{4}\)\(=\) \( 29 \beta_{9} - 302 \beta_{8} + 2 \beta_{7} - 3 \beta_{6} - 29 \beta_{5} + 38834 \beta_{4} - 301 \beta_{3} + \cdots - 38834 \) Copy content Toggle raw display
\(\nu^{5}\)\(=\) \( 412 \beta_{9} - 776 \beta_{8} + 1236 \beta_{7} - 412 \beta_{6} + 26500 \beta_{4} + 412 \beta_{3} + \cdots - 60821 \beta_1 \) Copy content Toggle raw display
\(\nu^{6}\)\(=\) \( 364\beta_{8} + 364\beta_{7} + 728\beta_{6} + 11900\beta_{5} + 87869\beta_{3} - 127740\beta_{2} + 9993185 \) Copy content Toggle raw display
\(\nu^{7}\)\(=\) \( - 131941 \beta_{9} + 412095 \beta_{8} - 266570 \beta_{7} + 399855 \beta_{6} + 131941 \beta_{5} + \cdots + 17760607 \) Copy content Toggle raw display
\(\nu^{8}\)\(=\) \( - 3873473 \beta_{9} + 25147837 \beta_{8} - 420447 \beta_{7} + 140149 \beta_{6} - 2700590774 \beta_{4} + \cdots + 52459845 \beta_1 \) Copy content Toggle raw display
\(\nu^{9}\)\(=\) \( - 39940984 \beta_{8} - 39940984 \beta_{7} - 79881968 \beta_{6} - 40131832 \beta_{5} - 136312296 \beta_{3} + \cdots - 7673460616 \) Copy content Toggle raw display

Character values

We give the values of \(\chi\) on generators for \(\left(\mathbb{Z}/21\mathbb{Z}\right)^\times\).

\(n\) \(8\) \(10\)
\(\chi(n)\) \(1\) \(-1 + \beta_{4}\)

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   \(\iota_m(\nu)\) \( a_{2} \) \( a_{3} \) \( a_{4} \) \( a_{5} \) \( a_{6} \) \( a_{7} \) \( a_{8} \) \( a_{9} \) \( a_{10} \)
4.1
8.58614 + 14.8716i
5.14307 + 8.90806i
0.647883 + 1.12217i
−6.17442 10.6944i
−8.20267 14.2074i
8.58614 14.8716i
5.14307 8.90806i
0.647883 1.12217i
−6.17442 + 10.6944i
−8.20267 + 14.2074i
−10.0861 17.4697i 13.5000 23.3827i −139.460 + 241.552i 214.749 + 371.955i −544.651 −617.628 + 664.890i 3044.41 −364.500 631.333i 4331.97 7503.19i
4.2 −6.64307 11.5061i 13.5000 23.3827i −24.2608 + 42.0210i −174.171 301.672i −358.726 899.874 117.341i −1055.96 −364.500 631.333i −2314.06 + 4008.06i
4.3 −2.14788 3.72024i 13.5000 23.3827i 54.7732 94.8700i 120.528 + 208.761i −115.986 −243.986 874.079i −1020.44 −364.500 631.333i 517.760 896.787i
4.4 4.67442 + 8.09634i 13.5000 23.3827i 20.2996 35.1599i −204.050 353.424i 252.419 −796.201 435.438i 1576.21 −364.500 631.333i 1907.63 3304.11i
4.5 6.70267 + 11.6094i 13.5000 23.3827i −25.8516 + 44.7763i 141.943 + 245.853i 361.944 328.441 + 845.973i 1022.78 −364.500 631.333i −1902.80 + 3295.75i
16.1 −10.0861 + 17.4697i 13.5000 + 23.3827i −139.460 241.552i 214.749 371.955i −544.651 −617.628 664.890i 3044.41 −364.500 + 631.333i 4331.97 + 7503.19i
16.2 −6.64307 + 11.5061i 13.5000 + 23.3827i −24.2608 42.0210i −174.171 + 301.672i −358.726 899.874 + 117.341i −1055.96 −364.500 + 631.333i −2314.06 4008.06i
16.3 −2.14788 + 3.72024i 13.5000 + 23.3827i 54.7732 + 94.8700i 120.528 208.761i −115.986 −243.986 + 874.079i −1020.44 −364.500 + 631.333i 517.760 + 896.787i
16.4 4.67442 8.09634i 13.5000 + 23.3827i 20.2996 + 35.1599i −204.050 + 353.424i 252.419 −796.201 + 435.438i 1576.21 −364.500 + 631.333i 1907.63 + 3304.11i
16.5 6.70267 11.6094i 13.5000 + 23.3827i −25.8516 44.7763i 141.943 245.853i 361.944 328.441 845.973i 1022.78 −364.500 + 631.333i −1902.80 3295.75i
\(n\): e.g. 2-40 or 990-1000
Embeddings: e.g. 1-3 or 4.5
Significant digits:
Format:

Inner twists

Char Parity Ord Mult Type
1.a even 1 1 trivial
7.c even 3 1 inner

Twists

       By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 21.8.e.b 10
3.b odd 2 1 63.8.e.d 10
7.b odd 2 1 147.8.e.n 10
7.c even 3 1 inner 21.8.e.b 10
7.c even 3 1 147.8.a.j 5
7.d odd 6 1 147.8.a.k 5
7.d odd 6 1 147.8.e.n 10
21.g even 6 1 441.8.a.w 5
21.h odd 6 1 63.8.e.d 10
21.h odd 6 1 441.8.a.x 5
    
        By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
21.8.e.b 10 1.a even 1 1 trivial
21.8.e.b 10 7.c even 3 1 inner
63.8.e.d 10 3.b odd 2 1
63.8.e.d 10 21.h odd 6 1
147.8.a.j 5 7.c even 3 1
147.8.a.k 5 7.d odd 6 1
147.8.e.n 10 7.b odd 2 1
147.8.e.n 10 7.d odd 6 1
441.8.a.w 5 21.g even 6 1
441.8.a.x 5 21.h odd 6 1

Hecke kernels

This newform subspace can be constructed as the kernel of the linear operator \( T_{2}^{10} + 15 T_{2}^{9} + 547 T_{2}^{8} + 2142 T_{2}^{7} + 130570 T_{2}^{6} + 504660 T_{2}^{5} + \cdots + 20819026944 \) acting on \(S_{8}^{\mathrm{new}}(21, [\chi])\). Copy content Toggle raw display

Hecke characteristic polynomials

$p$ $F_p(T)$
$2$ \( T^{10} + \cdots + 20819026944 \) Copy content Toggle raw display
$3$ \( (T^{2} - 27 T + 729)^{5} \) Copy content Toggle raw display
$5$ \( T^{10} + \cdots + 17\!\cdots\!00 \) Copy content Toggle raw display
$7$ \( T^{10} + \cdots + 37\!\cdots\!43 \) Copy content Toggle raw display
$11$ \( T^{10} + \cdots + 16\!\cdots\!00 \) Copy content Toggle raw display
$13$ \( (T^{5} + \cdots + 19\!\cdots\!84)^{2} \) Copy content Toggle raw display
$17$ \( T^{10} + \cdots + 72\!\cdots\!00 \) Copy content Toggle raw display
$19$ \( T^{10} + \cdots + 26\!\cdots\!16 \) Copy content Toggle raw display
$23$ \( T^{10} + \cdots + 15\!\cdots\!00 \) Copy content Toggle raw display
$29$ \( (T^{5} + \cdots - 51\!\cdots\!88)^{2} \) Copy content Toggle raw display
$31$ \( T^{10} + \cdots + 59\!\cdots\!61 \) Copy content Toggle raw display
$37$ \( T^{10} + \cdots + 32\!\cdots\!44 \) Copy content Toggle raw display
$41$ \( (T^{5} + \cdots + 10\!\cdots\!00)^{2} \) Copy content Toggle raw display
$43$ \( (T^{5} + \cdots - 21\!\cdots\!80)^{2} \) Copy content Toggle raw display
$47$ \( T^{10} + \cdots + 24\!\cdots\!00 \) Copy content Toggle raw display
$53$ \( T^{10} + \cdots + 49\!\cdots\!36 \) Copy content Toggle raw display
$59$ \( T^{10} + \cdots + 65\!\cdots\!00 \) Copy content Toggle raw display
$61$ \( T^{10} + \cdots + 33\!\cdots\!00 \) Copy content Toggle raw display
$67$ \( T^{10} + \cdots + 71\!\cdots\!00 \) Copy content Toggle raw display
$71$ \( (T^{5} + \cdots - 37\!\cdots\!12)^{2} \) Copy content Toggle raw display
$73$ \( T^{10} + \cdots + 23\!\cdots\!36 \) Copy content Toggle raw display
$79$ \( T^{10} + \cdots + 53\!\cdots\!81 \) Copy content Toggle raw display
$83$ \( (T^{5} + \cdots - 83\!\cdots\!56)^{2} \) Copy content Toggle raw display
$89$ \( T^{10} + \cdots + 12\!\cdots\!56 \) Copy content Toggle raw display
$97$ \( (T^{5} + \cdots - 10\!\cdots\!28)^{2} \) Copy content Toggle raw display
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