Properties

Label 81.8.c.f
Level $81$
Weight $8$
Character orbit 81.c
Analytic conductor $25.303$
Analytic rank $0$
Dimension $4$
Inner twists $4$

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Newspace parameters

Copy content comment:Compute space of new eigenforms
 
Copy content gp:[N,k,chi] = [81,8,Mod(28,81)] 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("81.28"); S:= CuspForms(chi, 8); N := Newforms(S);
 
Copy content sage:from sage.modular.dirichlet import DirichletCharacter H = DirichletGroup(81, base_ring=CyclotomicField(6)) chi = DirichletCharacter(H, H._module([2])) N = Newforms(chi, 8, names="a")
 
Level: \( N \) \(=\) \( 81 = 3^{4} \)
Weight: \( k \) \(=\) \( 8 \)
Character orbit: \([\chi]\) \(=\) 81.c (of order \(3\), degree \(2\), not minimal)

Newform invariants

Copy content comment:select newform
 
Copy content sage:traces = [4,0,0,-464] 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: \(25.3031870642\)
Analytic rank: \(0\)
Dimension: \(4\)
Relative dimension: \(2\) over \(\Q(\zeta_{3})\)
Coefficient field: \(\Q(\sqrt{-3}, \sqrt{10})\)
Copy content comment:defining polynomial
 
Copy content gp:f.mod \\ as an extension of the character field
 
Defining polynomial: \( x^{4} + 10x^{2} + 100 \) Copy content Toggle raw display
Coefficient ring: \(\Z[a_1, \ldots, a_{25}]\)
Coefficient ring index: \( 2^{2}\cdot 3^{2} \)
Twist minimal: no (minimal twist has level 9)
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 \(1,\beta_1,\beta_2,\beta_3\) for the coefficient ring described below. We also show the integral \(q\)-expansion of the trace form.

\(f(q)\) \(=\) \( q + \beta_1 q^{2} + 232 \beta_{2} q^{4} + (16 \beta_{3} + 16 \beta_1) q^{5} + ( - 260 \beta_{2} - 260) q^{7} + 104 \beta_{3} q^{8} - 5760 q^{10} - 320 \beta_1 q^{11} + 6890 \beta_{2} q^{13} + ( - 260 \beta_{3} - 260 \beta_1) q^{14}+ \cdots - 755943 \beta_{3} q^{98}+O(q^{100}) \) Copy content Toggle raw display
\(\operatorname{Tr}(f)(q)\) \(=\) \( 4 q - 464 q^{4} - 520 q^{7} - 23040 q^{10} - 13780 q^{13} - 15488 q^{16} + 132704 q^{19} + 230400 q^{22} - 28070 q^{25} + 241280 q^{28} - 3016 q^{31} - 898560 q^{34} - 1523080 q^{37} + 1198080 q^{40} - 15280 q^{43}+ \cdots + 25914980 q^{97}+O(q^{100}) \) Copy content Toggle raw display

Basis of coefficient ring in terms of a root \(\nu\) of \( x^{4} + 10x^{2} + 100 \) : Copy content Toggle raw display

\(\beta_{1}\)\(=\) \( 6\nu \) Copy content Toggle raw display
\(\beta_{2}\)\(=\) \( ( \nu^{2} ) / 10 \) Copy content Toggle raw display
\(\beta_{3}\)\(=\) \( ( 3\nu^{3} ) / 5 \) Copy content Toggle raw display
\(\nu\)\(=\) \( ( \beta_1 ) / 6 \) Copy content Toggle raw display
\(\nu^{2}\)\(=\) \( 10\beta_{2} \) Copy content Toggle raw display
\(\nu^{3}\)\(=\) \( ( 5\beta_{3} ) / 3 \) Copy content Toggle raw display

Character values

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

\(n\) \(2\)
\(\chi(n)\) \(\beta_{2}\)

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   \(\iota_m(\nu)\) \( a_{2} \) \( a_{3} \) \( a_{4} \) \( a_{5} \) \( a_{6} \) \( a_{7} \) \( a_{8} \) \( a_{9} \) \( a_{10} \)
28.1
−1.58114 2.73861i
1.58114 + 2.73861i
−1.58114 + 2.73861i
1.58114 2.73861i
−9.48683 16.4317i 0 −116.000 + 200.918i 151.789 262.907i 0 −130.000 225.167i 1973.26 0 −5760.00
28.2 9.48683 + 16.4317i 0 −116.000 + 200.918i −151.789 + 262.907i 0 −130.000 225.167i −1973.26 0 −5760.00
55.1 −9.48683 + 16.4317i 0 −116.000 200.918i 151.789 + 262.907i 0 −130.000 + 225.167i 1973.26 0 −5760.00
55.2 9.48683 16.4317i 0 −116.000 200.918i −151.789 262.907i 0 −130.000 + 225.167i −1973.26 0 −5760.00
\(n\): 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
9.c even 3 1 inner
9.d odd 6 1 inner

Twists

       By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 81.8.c.f 4
3.b odd 2 1 inner 81.8.c.f 4
9.c even 3 1 9.8.a.b 2
9.c even 3 1 inner 81.8.c.f 4
9.d odd 6 1 9.8.a.b 2
9.d odd 6 1 inner 81.8.c.f 4
36.f odd 6 1 144.8.a.m 2
36.h even 6 1 144.8.a.m 2
45.h odd 6 1 225.8.a.q 2
45.j even 6 1 225.8.a.q 2
45.k odd 12 2 225.8.b.k 4
45.l even 12 2 225.8.b.k 4
63.l odd 6 1 441.8.a.k 2
63.o even 6 1 441.8.a.k 2
72.j odd 6 1 576.8.a.bj 2
72.l even 6 1 576.8.a.bi 2
72.n even 6 1 576.8.a.bj 2
72.p odd 6 1 576.8.a.bi 2
    
        By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
9.8.a.b 2 9.c even 3 1
9.8.a.b 2 9.d odd 6 1
81.8.c.f 4 1.a even 1 1 trivial
81.8.c.f 4 3.b odd 2 1 inner
81.8.c.f 4 9.c even 3 1 inner
81.8.c.f 4 9.d odd 6 1 inner
144.8.a.m 2 36.f odd 6 1
144.8.a.m 2 36.h even 6 1
225.8.a.q 2 45.h odd 6 1
225.8.a.q 2 45.j even 6 1
225.8.b.k 4 45.k odd 12 2
225.8.b.k 4 45.l even 12 2
441.8.a.k 2 63.l odd 6 1
441.8.a.k 2 63.o even 6 1
576.8.a.bi 2 72.l even 6 1
576.8.a.bi 2 72.p odd 6 1
576.8.a.bj 2 72.j odd 6 1
576.8.a.bj 2 72.n even 6 1

Hecke kernels

This newform subspace can be constructed as the kernel of the linear operator \( T_{2}^{4} + 360T_{2}^{2} + 129600 \) acting on \(S_{8}^{\mathrm{new}}(81, [\chi])\). Copy content Toggle raw display

Hecke characteristic polynomials

$p$ $F_p(T)$
$2$ \( T^{4} + 360 T^{2} + 129600 \) Copy content Toggle raw display
$3$ \( T^{4} \) Copy content Toggle raw display
$5$ \( T^{4} + \cdots + 8493465600 \) Copy content Toggle raw display
$7$ \( (T^{2} + 260 T + 67600)^{2} \) Copy content Toggle raw display
$11$ \( T^{4} + \cdots + 13\!\cdots\!00 \) Copy content Toggle raw display
$13$ \( (T^{2} + 6890 T + 47472100)^{2} \) Copy content Toggle raw display
$17$ \( (T^{2} - 560701440)^{2} \) Copy content Toggle raw display
$19$ \( (T - 33176)^{4} \) Copy content Toggle raw display
$23$ \( T^{4} + \cdots + 99\!\cdots\!00 \) Copy content Toggle raw display
$29$ \( T^{4} + \cdots + 36\!\cdots\!00 \) Copy content Toggle raw display
$31$ \( (T^{2} + 1508 T + 2274064)^{2} \) Copy content Toggle raw display
$37$ \( (T + 380770)^{4} \) Copy content Toggle raw display
$41$ \( T^{4} + \cdots + 60\!\cdots\!00 \) Copy content Toggle raw display
$43$ \( (T^{2} + 7640 T + 58369600)^{2} \) Copy content Toggle raw display
$47$ \( T^{4} + \cdots + 10\!\cdots\!00 \) Copy content Toggle raw display
$53$ \( (T^{2} - 1060987299840)^{2} \) Copy content Toggle raw display
$59$ \( T^{4} + \cdots + 53\!\cdots\!00 \) Copy content Toggle raw display
$61$ \( (T^{2} - 988858 T + 977840144164)^{2} \) Copy content Toggle raw display
$67$ \( (T^{2} + \cdots + 14879226169600)^{2} \) Copy content Toggle raw display
$71$ \( (T^{2} - 17857511424000)^{2} \) Copy content Toggle raw display
$73$ \( (T + 2004730)^{4} \) Copy content Toggle raw display
$79$ \( (T^{2} + \cdots + 7288293699856)^{2} \) Copy content Toggle raw display
$83$ \( T^{4} + \cdots + 54\!\cdots\!00 \) Copy content Toggle raw display
$89$ \( (T^{2} - 59927040000000)^{2} \) Copy content Toggle raw display
$97$ \( (T^{2} + \cdots + 167896547100100)^{2} \) Copy content Toggle raw display
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