Properties

Label 847.1.d.b
Level $847$
Weight $1$
Character orbit 847.d
Self dual yes
Analytic conductor $0.423$
Analytic rank $0$
Dimension $2$
Projective image $D_{5}$
CM discriminant -7
Inner twists $2$

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Show commands: Magma / PariGP / SageMath

Newspace parameters

comment: Compute space of new eigenforms
 
[N,k,chi] = [847,1,Mod(727,847)]
 
mf = mfinit([N,k,chi],0)
 
lf = mfeigenbasis(mf)
 
from sage.modular.dirichlet import DirichletCharacter
 
H = DirichletGroup(847, base_ring=CyclotomicField(2))
 
chi = DirichletCharacter(H, H._module([1, 0]))
 
N = Newforms(chi, 1, names="a")
 
//Please install CHIMP (https://github.com/edgarcosta/CHIMP) if you want to run this code
 
chi := DirichletCharacter("847.727");
 
S:= CuspForms(chi, 1);
 
N := Newforms(S);
 
Level: \( N \) \(=\) \( 847 = 7 \cdot 11^{2} \)
Weight: \( k \) \(=\) \( 1 \)
Character orbit: \([\chi]\) \(=\) 847.d (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: yes
Analytic conductor: \(0.422708065700\)
Analytic rank: \(0\)
Dimension: \(2\)
Coefficient field: \(\Q(\sqrt{5}) \)
comment: defining polynomial
 
gp: f.mod \\ as an extension of the character field
 
Defining polynomial: \( x^{2} - x - 1 \) Copy content Toggle raw display
Coefficient ring: \(\Z[a_1, a_2]\)
Coefficient ring index: \( 1 \)
Twist minimal: no (minimal twist has level 77)
Projective image: \(D_{5}\)
Projective field: Galois closure of 5.1.717409.1

$q$-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 \(\beta = \frac{1}{2}(1 + \sqrt{5})\). We also show the integral \(q\)-expansion of the trace form.

\(f(q)\) \(=\) \( q + ( - \beta + 1) q^{2} + ( - \beta + 1) q^{4} - q^{7} + q^{8} + q^{9}+O(q^{10}) \) Copy content Toggle raw display \( q + ( - \beta + 1) q^{2} + ( - \beta + 1) q^{4} - q^{7} + q^{8} + q^{9} + (\beta - 1) q^{14} + ( - \beta + 1) q^{18} + (\beta - 1) q^{23} + q^{25} + (\beta - 1) q^{28} + \beta q^{29} - q^{32} + ( - \beta + 1) q^{36} + (\beta - 1) q^{37} + \beta q^{43} + (\beta - 2) q^{46} + q^{49} + ( - \beta + 1) q^{50} - \beta q^{53} - q^{56} - q^{58} - q^{63} + (\beta - 1) q^{64} - \beta q^{67} - \beta q^{71} + q^{72} + (\beta - 2) q^{74} + \beta q^{79} + q^{81} - q^{86} + (\beta - 2) q^{92} + ( - \beta + 1) q^{98} +O(q^{100}) \) Copy content Toggle raw display
\(\operatorname{Tr}(f)(q)\) \(=\) \( 2 q + q^{2} + q^{4} - 2 q^{7} + 2 q^{8} + 2 q^{9}+O(q^{10}) \) Copy content Toggle raw display \( 2 q + q^{2} + q^{4} - 2 q^{7} + 2 q^{8} + 2 q^{9} - q^{14} + q^{18} - q^{23} + 2 q^{25} - q^{28} + q^{29} - 2 q^{32} + q^{36} - q^{37} + q^{43} - 3 q^{46} + 2 q^{49} + q^{50} - q^{53} - 2 q^{56} - 2 q^{58} - 2 q^{63} - q^{64} - q^{67} - q^{71} + 2 q^{72} - 3 q^{74} + q^{79} + 2 q^{81} - 2 q^{86} - 3 q^{92} + q^{98}+O(q^{100}) \) Copy content Toggle raw display

Character values

We give the values of \(\chi\) on generators for \(\left(\mathbb{Z}/847\mathbb{Z}\right)^\times\).

\(n\) \(122\) \(365\)
\(\chi(n)\) \(-1\) \(1\)

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   \(\iota_m(\nu)\) \( a_{2} \) \( a_{3} \) \( a_{4} \) \( a_{5} \) \( a_{6} \) \( a_{7} \) \( a_{8} \) \( a_{9} \) \( a_{10} \)
727.1
1.61803
−0.618034
−0.618034 0 −0.618034 0 0 −1.00000 1.00000 1.00000 0
727.2 1.61803 0 1.61803 0 0 −1.00000 1.00000 1.00000 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 CM by \(\Q(\sqrt{-7}) \)

Twists

       By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 847.1.d.b 2
7.b odd 2 1 CM 847.1.d.b 2
11.b odd 2 1 847.1.d.a 2
11.c even 5 2 847.1.j.a 4
11.c even 5 2 847.1.j.b 4
11.d odd 10 2 77.1.j.a 4
11.d odd 10 2 847.1.j.c 4
33.f even 10 2 693.1.br.a 4
44.g even 10 2 1232.1.cd.a 4
55.h odd 10 2 1925.1.bn.a 4
55.l even 20 4 1925.1.cb.a 8
77.b even 2 1 847.1.d.a 2
77.j odd 10 2 847.1.j.a 4
77.j odd 10 2 847.1.j.b 4
77.l even 10 2 77.1.j.a 4
77.l even 10 2 847.1.j.c 4
77.n even 30 4 539.1.u.a 8
77.o odd 30 4 539.1.u.a 8
231.r odd 10 2 693.1.br.a 4
308.s odd 10 2 1232.1.cd.a 4
385.v even 10 2 1925.1.bn.a 4
385.bi odd 20 4 1925.1.cb.a 8
    
        By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
77.1.j.a 4 11.d odd 10 2
77.1.j.a 4 77.l even 10 2
539.1.u.a 8 77.n even 30 4
539.1.u.a 8 77.o odd 30 4
693.1.br.a 4 33.f even 10 2
693.1.br.a 4 231.r odd 10 2
847.1.d.a 2 11.b odd 2 1
847.1.d.a 2 77.b even 2 1
847.1.d.b 2 1.a even 1 1 trivial
847.1.d.b 2 7.b odd 2 1 CM
847.1.j.a 4 11.c even 5 2
847.1.j.a 4 77.j odd 10 2
847.1.j.b 4 11.c even 5 2
847.1.j.b 4 77.j odd 10 2
847.1.j.c 4 11.d odd 10 2
847.1.j.c 4 77.l even 10 2
1232.1.cd.a 4 44.g even 10 2
1232.1.cd.a 4 308.s odd 10 2
1925.1.bn.a 4 55.h odd 10 2
1925.1.bn.a 4 385.v even 10 2
1925.1.cb.a 8 55.l even 20 4
1925.1.cb.a 8 385.bi odd 20 4

Hecke kernels

This newform subspace can be constructed as the kernel of the linear operator \( T_{2}^{2} - T_{2} - 1 \) acting on \(S_{1}^{\mathrm{new}}(847, [\chi])\). Copy content Toggle raw display

Hecke characteristic polynomials

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