Properties

Label 841.2.b.b
Level $841$
Weight $2$
Character orbit 841.b
Analytic conductor $6.715$
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] = [841,2,Mod(840,841)] 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("841.840"); S:= CuspForms(chi, 2); N := Newforms(S);
 
Copy content sage:from sage.modular.dirichlet import DirichletCharacter H = DirichletGroup(841, base_ring=CyclotomicField(2)) chi = DirichletCharacter(H, H._module([1])) N = Newforms(chi, 2, names="a")
 
Level: \( N \) \(=\) \( 841 = 29^{2} \)
Weight: \( k \) \(=\) \( 2 \)
Character orbit: \([\chi]\) \(=\) 841.b (of order \(2\), degree \(1\), not minimal)

Newform invariants

Copy content comment:select newform
 
Copy content sage:traces = [4,0,0,2] f = next(g for g in N if [g.coefficient(i+1).trace() for i in range(4)] == traces)
 
Copy content gp:f = lf[1] \\ Warning: the index may be different
 
Self dual: no
Analytic conductor: \(6.71541880999\)
Analytic rank: \(0\)
Dimension: \(4\)
Coefficient field: \(\Q(i, \sqrt{5})\)
Copy content comment:defining polynomial
 
Copy content gp:f.mod \\ as an extension of the character field
 
Defining polynomial: \( x^{4} + 3x^{2} + 1 \) Copy content Toggle raw display
Coefficient ring: \(\Z[a_1, a_2]\)
Coefficient ring index: \( 1 \)
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.

\(f(q)\) \(=\) \( q + \beta_1 q^{2} - \beta_1 q^{3} + (\beta_{2} + 1) q^{4} + ( - 3 \beta_{2} - 2) q^{5} + ( - \beta_{2} + 1) q^{6} + ( - 2 \beta_{2} - 1) q^{7} + (\beta_{3} + 2 \beta_1) q^{8} + (\beta_{2} + 2) q^{9} + ( - 3 \beta_{3} + \beta_1) q^{10}+ \cdots + ( - 3 \beta_{3} - \beta_1) q^{99}+O(q^{100}) \) Copy content Toggle raw display
\(\operatorname{Tr}(f)(q)\) \(=\) \( 4 q + 2 q^{4} - 2 q^{5} + 6 q^{6} + 6 q^{9} - 8 q^{13} - 6 q^{16} - 16 q^{20} - 10 q^{22} + 4 q^{23} + 10 q^{24} + 26 q^{25} - 10 q^{28} + 12 q^{30} + 10 q^{33} - 16 q^{34} + 30 q^{35} + 8 q^{36} + 12 q^{38}+ \cdots - 4 q^{96}+O(q^{100}) \) Copy content Toggle raw display

Basis of coefficient ring in terms of a root \(\nu\) of \( x^{4} + 3x^{2} + 1 \) : Copy content Toggle raw display

\(\beta_{1}\)\(=\) \( \nu \) Copy content Toggle raw display
\(\beta_{2}\)\(=\) \( \nu^{2} + 1 \) Copy content Toggle raw display
\(\beta_{3}\)\(=\) \( \nu^{3} + 2\nu \) Copy content Toggle raw display
\(\nu\)\(=\) \( \beta_1 \) Copy content Toggle raw display
\(\nu^{2}\)\(=\) \( \beta_{2} - 1 \) 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 \(\left(\mathbb{Z}/841\mathbb{Z}\right)^\times\).

\(n\) \(2\)
\(\chi(n)\) \(-1\)

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   \(\iota_m(\nu)\) \( a_{2} \) \( a_{3} \) \( a_{4} \) \( a_{5} \) \( a_{6} \) \( a_{7} \) \( a_{8} \) \( a_{9} \) \( a_{10} \)
840.1
1.61803i
0.618034i
0.618034i
1.61803i
1.61803i 1.61803i −0.618034 2.85410 2.61803 2.23607 2.23607i 0.381966 4.61803i
840.2 0.618034i 0.618034i 1.61803 −3.85410 0.381966 −2.23607 2.23607i 2.61803 2.38197i
840.3 0.618034i 0.618034i 1.61803 −3.85410 0.381966 −2.23607 2.23607i 2.61803 2.38197i
840.4 1.61803i 1.61803i −0.618034 2.85410 2.61803 2.23607 2.23607i 0.381966 4.61803i
\(n\): e.g. 2-40 or 990-1000
Significant digits:
Format:

Inner twists

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

Twists

       By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 841.2.b.b 4
29.b even 2 1 inner 841.2.b.b 4
29.c odd 4 1 841.2.a.a 2
29.c odd 4 1 841.2.a.c yes 2
29.d even 7 6 841.2.e.j 24
29.e even 14 6 841.2.e.j 24
29.f odd 28 6 841.2.d.g 12
29.f odd 28 6 841.2.d.i 12
87.f even 4 1 7569.2.a.d 2
87.f even 4 1 7569.2.a.l 2
    
        By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
841.2.a.a 2 29.c odd 4 1
841.2.a.c yes 2 29.c odd 4 1
841.2.b.b 4 1.a even 1 1 trivial
841.2.b.b 4 29.b even 2 1 inner
841.2.d.g 12 29.f odd 28 6
841.2.d.i 12 29.f odd 28 6
841.2.e.j 24 29.d even 7 6
841.2.e.j 24 29.e even 14 6
7569.2.a.d 2 87.f even 4 1
7569.2.a.l 2 87.f even 4 1

Hecke kernels

This newform subspace can be constructed as the kernel of the linear operator \( T_{2}^{4} + 3T_{2}^{2} + 1 \) acting on \(S_{2}^{\mathrm{new}}(841, [\chi])\). Copy content Toggle raw display

Hecke characteristic polynomials

$p$ $F_p(T)$
$2$ \( T^{4} + 3T^{2} + 1 \) Copy content Toggle raw display
$3$ \( T^{4} + 3T^{2} + 1 \) Copy content Toggle raw display
$5$ \( (T^{2} + T - 11)^{2} \) Copy content Toggle raw display
$7$ \( (T^{2} - 5)^{2} \) Copy content Toggle raw display
$11$ \( T^{4} + 15T^{2} + 25 \) Copy content Toggle raw display
$13$ \( (T^{2} + 4 T - 1)^{2} \) Copy content Toggle raw display
$17$ \( T^{4} + 63T^{2} + 841 \) Copy content Toggle raw display
$19$ \( T^{4} + 27T^{2} + 81 \) Copy content Toggle raw display
$23$ \( (T^{2} - 2 T - 4)^{2} \) Copy content Toggle raw display
$29$ \( T^{4} \) Copy content Toggle raw display
$31$ \( T^{4} + 103T^{2} + 121 \) Copy content Toggle raw display
$37$ \( T^{4} + 98T^{2} + 1681 \) Copy content Toggle raw display
$41$ \( T^{4} + 23T^{2} + 121 \) Copy content Toggle raw display
$43$ \( T^{4} + 60T^{2} + 400 \) Copy content Toggle raw display
$47$ \( (T^{2} + 49)^{2} \) Copy content Toggle raw display
$53$ \( (T + 2)^{4} \) Copy content Toggle raw display
$59$ \( (T^{2} - T - 31)^{2} \) Copy content Toggle raw display
$61$ \( T^{4} + 3T^{2} + 1 \) Copy content Toggle raw display
$67$ \( (T^{2} - 12 T + 16)^{2} \) Copy content Toggle raw display
$71$ \( (T^{2} + 12 T + 16)^{2} \) Copy content Toggle raw display
$73$ \( T^{4} + 188T^{2} + 16 \) Copy content Toggle raw display
$79$ \( T^{4} + 63T^{2} + 961 \) Copy content Toggle raw display
$83$ \( (T^{2} + 2 T - 79)^{2} \) Copy content Toggle raw display
$89$ \( T^{4} + 98T^{2} + 1681 \) Copy content Toggle raw display
$97$ \( T^{4} + 287T^{2} + 3481 \) Copy content Toggle raw display
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