Properties

Label 81.3.b.b
Level $81$
Weight $3$
Character orbit 81.b
Analytic conductor $2.207$
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] = [81,3,Mod(80,81)] mf = mfinit([N,k,chi],0) lf = mfeigenbasis(mf)
 
Copy content sage:from sage.modular.dirichlet import DirichletCharacter H = DirichletGroup(81, base_ring=CyclotomicField(2)) chi = DirichletCharacter(H, H._module([1])) N = Newforms(chi, 3, names="a")
 
Copy content magma://Please install CHIMP (https://github.com/edgarcosta/CHIMP) if you want to run this code chi := DirichletCharacter("81.80"); S:= CuspForms(chi, 3); N := Newforms(S);
 
Level: \( N \) \(=\) \( 81 = 3^{4} \)
Weight: \( k \) \(=\) \( 3 \)
Character orbit: \([\chi]\) \(=\) 81.b (of order \(2\), degree \(1\), minimal)

Newform invariants

Copy content comment:select newform
 
Copy content sage:traces = [4] 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: \(2.20709014132\)
Analytic rank: \(0\)
Dimension: \(4\)
Coefficient field: \(\Q(\sqrt{-2}, \sqrt{3})\)
Copy content comment:defining polynomial
 
Copy content gp:f.mod \\ as an extension of the character field
 
Defining polynomial: \( x^{4} + 4x^{2} + 1 \) Copy content Toggle raw display
Coefficient ring: \(\Z[a_1, a_2]\)
Coefficient ring index: \( 3^{3} \)
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.

\(f(q)\) \(=\) \( q + \beta_1 q^{2} + (\beta_{3} - 2) q^{4} + ( - \beta_{2} + \beta_1) q^{5} + (\beta_{3} - 1) q^{7} + (\beta_{2} - 3 \beta_1) q^{8} + (2 \beta_{3} - 3) q^{10} + (\beta_{2} + 2 \beta_1) q^{11} + ( - 2 \beta_{3} + 11) q^{13}+ \cdots + ( - 2 \beta_{2} - 11 \beta_1) q^{98}+O(q^{100}) \) Copy content Toggle raw display
\(\operatorname{Tr}(f)(q)\) \(=\) \( 4 q - 8 q^{4} - 4 q^{7} - 12 q^{10} + 44 q^{13} + 28 q^{16} - 28 q^{19} - 60 q^{22} - 68 q^{25} + 116 q^{28} - 64 q^{31} + 36 q^{34} + 8 q^{37} + 192 q^{40} + 140 q^{43} - 300 q^{46} - 84 q^{49} - 304 q^{52}+ \cdots + 32 q^{97}+O(q^{100}) \) Copy content Toggle raw display

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

\(\beta_{1}\)\(=\) \( \nu^{3} + 2\nu \) Copy content Toggle raw display
\(\beta_{2}\)\(=\) \( 5\nu^{3} + 19\nu \) Copy content Toggle raw display
\(\beta_{3}\)\(=\) \( 3\nu^{2} + 6 \) Copy content Toggle raw display
\(\nu\)\(=\) \( ( \beta_{2} - 5\beta_1 ) / 9 \) Copy content Toggle raw display
\(\nu^{2}\)\(=\) \( ( \beta_{3} - 6 ) / 3 \) Copy content Toggle raw display
\(\nu^{3}\)\(=\) \( ( -2\beta_{2} + 19\beta_1 ) / 9 \) Copy content Toggle raw display

Character values

We give the values of \(\chi\) on generators for \(\left(\mathbb{Z}/81\mathbb{Z}\right)^\times\).

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

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   \(\iota_m(\nu)\) \( a_{2} \) \( a_{3} \) \( a_{4} \) \( a_{5} \) \( a_{6} \) \( a_{7} \) \( a_{8} \) \( a_{9} \) \( a_{10} \)
80.1
1.93185i
0.517638i
0.517638i
1.93185i
3.34607i 0 −7.19615 4.00240i 0 −6.19615 10.6945i 0 −13.3923
80.2 0.896575i 0 3.19615 8.24504i 0 4.19615 6.45189i 0 7.39230
80.3 0.896575i 0 3.19615 8.24504i 0 4.19615 6.45189i 0 7.39230
80.4 3.34607i 0 −7.19615 4.00240i 0 −6.19615 10.6945i 0 −13.3923
\(n\): e.g. 2-40 or 990-1000
Significant digits:
Format:

Inner twists

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

Twists

       By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 81.3.b.b 4
3.b odd 2 1 inner 81.3.b.b 4
4.b odd 2 1 1296.3.e.h 4
9.c even 3 2 81.3.d.c 8
9.d odd 6 2 81.3.d.c 8
12.b even 2 1 1296.3.e.h 4
36.f odd 6 2 1296.3.q.m 8
36.h even 6 2 1296.3.q.m 8
    
        By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
81.3.b.b 4 1.a even 1 1 trivial
81.3.b.b 4 3.b odd 2 1 inner
81.3.d.c 8 9.c even 3 2
81.3.d.c 8 9.d odd 6 2
1296.3.e.h 4 4.b odd 2 1
1296.3.e.h 4 12.b even 2 1
1296.3.q.m 8 36.f odd 6 2
1296.3.q.m 8 36.h even 6 2

Hecke kernels

This newform subspace can be constructed as the kernel of the linear operator \( T_{2}^{4} + 12T_{2}^{2} + 9 \) acting on \(S_{3}^{\mathrm{new}}(81, [\chi])\). Copy content Toggle raw display

Hecke characteristic polynomials

$p$ $F_p(T)$
$2$ \( T^{4} + 12T^{2} + 9 \) Copy content Toggle raw display
$3$ \( T^{4} \) Copy content Toggle raw display
$5$ \( T^{4} + 84T^{2} + 1089 \) Copy content Toggle raw display
$7$ \( (T^{2} + 2 T - 26)^{2} \) Copy content Toggle raw display
$11$ \( T^{4} + 156T^{2} + 4356 \) Copy content Toggle raw display
$13$ \( (T^{2} - 22 T + 13)^{2} \) Copy content Toggle raw display
$17$ \( T^{4} + 108T^{2} + 729 \) Copy content Toggle raw display
$19$ \( (T^{2} + 14 T - 194)^{2} \) Copy content Toggle raw display
$23$ \( T^{4} + 1956 T^{2} + 617796 \) Copy content Toggle raw display
$29$ \( T^{4} + 12T^{2} + 9 \) Copy content Toggle raw display
$31$ \( (T^{2} + 32 T + 148)^{2} \) Copy content Toggle raw display
$37$ \( (T^{2} - 4 T - 239)^{2} \) Copy content Toggle raw display
$41$ \( T^{4} + 2316 T^{2} + 1313316 \) Copy content Toggle raw display
$43$ \( (T^{2} - 70 T + 1198)^{2} \) Copy content Toggle raw display
$47$ \( T^{4} + 7536 T^{2} + 13927824 \) Copy content Toggle raw display
$53$ \( (T^{2} + 4374)^{2} \) Copy content Toggle raw display
$59$ \( T^{4} + 1488 T^{2} + 24336 \) Copy content Toggle raw display
$61$ \( (T^{2} - 88 T + 1261)^{2} \) Copy content Toggle raw display
$67$ \( (T^{2} - 58 T - 8906)^{2} \) Copy content Toggle raw display
$71$ \( T^{4} + 7236 T^{2} + 10850436 \) Copy content Toggle raw display
$73$ \( (T^{2} + 32 T - 1931)^{2} \) Copy content Toggle raw display
$79$ \( (T^{2} + 182 T + 8254)^{2} \) Copy content Toggle raw display
$83$ \( T^{4} + 17616 T^{2} + 74235456 \) Copy content Toggle raw display
$89$ \( T^{4} + 29268 T^{2} + 213364449 \) Copy content Toggle raw display
$97$ \( (T^{2} - 16 T - 2636)^{2} \) Copy content Toggle raw display
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