Newspace parameters
comment: Compute space of new eigenforms
[N,k,chi] = [840,4,Mod(1,840)]
mf = mfinit([N,k,chi],0)
lf = mfeigenbasis(mf)
from sage.modular.dirichlet import DirichletCharacter
H = DirichletGroup(840, base_ring=CyclotomicField(2))
chi = DirichletCharacter(H, H._module([0, 0, 0, 0, 0]))
N = Newforms(chi, 4, names="a")
//Please install CHIMP (https://github.com/edgarcosta/CHIMP) if you want to run this code
chi := DirichletCharacter("840.1");
S:= CuspForms(chi, 4);
N := Newforms(S);
| Level: | \( N \) | \(=\) | \( 840 = 2^{3} \cdot 3 \cdot 5 \cdot 7 \) |
| Weight: | \( k \) | \(=\) | \( 4 \) |
| Character orbit: | \([\chi]\) | \(=\) | 840.a (trivial) |
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: | \(49.5616044048\) |
| Analytic rank: | \(1\) |
| Dimension: | \(2\) |
| Coefficient field: | \(\Q(\sqrt{21}) \) |
|
comment: defining polynomial
gp: f.mod \\ as an extension of the character field
|
|
| Defining polynomial: |
\( x^{2} - x - 5 \)
|
| Coefficient ring: | \(\Z[a_1, \ldots, a_{13}]\) |
| Coefficient ring index: | \( 2^{2} \) |
| Twist minimal: | yes |
| Fricke sign: | \(-1\) |
| Sato-Tate group: | $\mathrm{SU}(2)$ |
$q$-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 \(\beta = 2\sqrt{21}\). We also show the integral \(q\)-expansion of the trace form.
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 | \(\iota_m(\nu)\) | \( a_{2} \) | \( a_{3} \) | \( a_{4} \) | \( a_{5} \) | \( a_{6} \) | \( a_{7} \) | \( a_{8} \) | \( a_{9} \) | \( a_{10} \) | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1.1 |
|
0 | 3.00000 | 0 | −5.00000 | 0 | −7.00000 | 0 | 9.00000 | 0 | ||||||||||||||||||||||||
| 1.2 | 0 | 3.00000 | 0 | −5.00000 | 0 | −7.00000 | 0 | 9.00000 | 0 | |||||||||||||||||||||||||
Atkin-Lehner signs
| \( p \) | Sign |
|---|---|
| \(2\) | \( +1 \) |
| \(3\) | \( -1 \) |
| \(5\) | \( +1 \) |
| \(7\) | \( +1 \) |
Inner twists
This newform does not admit any (nontrivial) inner twists.
Twists
| By twisting character orbit | |||||||
|---|---|---|---|---|---|---|---|
| Char | Parity | Ord | Mult | Type | Twist | Min | Dim |
| 1.a | even | 1 | 1 | trivial | 840.4.a.m | ✓ | 2 |
| 4.b | odd | 2 | 1 | 1680.4.a.ba | 2 | ||
| By twisted newform orbit | |||||||
|---|---|---|---|---|---|---|---|
| Twist | Min | Dim | Char | Parity | Ord | Mult | Type |
| 840.4.a.m | ✓ | 2 | 1.a | even | 1 | 1 | trivial |
| 1680.4.a.ba | 2 | 4.b | odd | 2 | 1 | ||
Hecke kernels
This newform subspace can be constructed as the kernel of the linear operator
\( T_{11}^{2} - 28T_{11} - 560 \)
acting on \(S_{4}^{\mathrm{new}}(\Gamma_0(840))\).
Hecke characteristic polynomials
| $p$ | $F_p(T)$ |
|---|---|
| $2$ |
\( T^{2} \)
|
| $3$ |
\( (T - 3)^{2} \)
|
| $5$ |
\( (T + 5)^{2} \)
|
| $7$ |
\( (T + 7)^{2} \)
|
| $11$ |
\( T^{2} - 28T - 560 \)
|
| $13$ |
\( T^{2} + 16T - 20 \)
|
| $17$ |
\( T^{2} + 12T - 2988 \)
|
| $19$ |
\( T^{2} - 12T - 10128 \)
|
| $23$ |
\( T^{2} + 144T - 3216 \)
|
| $29$ |
\( T^{2} + 12T - 8364 \)
|
| $31$ |
\( T^{2} + 84T - 59472 \)
|
| $37$ |
\( T^{2} + 276T + 17700 \)
|
| $41$ |
\( T^{2} - 92T - 9980 \)
|
| $43$ |
\( T^{2} + 120T - 1776 \)
|
| $47$ |
\( T^{2} + 480T + 52224 \)
|
| $53$ |
\( T^{2} + 648T + 94812 \)
|
| $59$ |
\( T^{2} + 784T - 24080 \)
|
| $61$ |
\( T^{2} + 668T - 9740 \)
|
| $67$ |
\( T^{2} + 368T - 426128 \)
|
| $71$ |
\( T^{2} + 28T - 292208 \)
|
| $73$ |
\( T^{2} + 1120T + 40684 \)
|
| $79$ |
\( T^{2} + 888T + 156480 \)
|
| $83$ |
\( T^{2} + 1200 T + 262896 \)
|
| $89$ |
\( T^{2} - 188 T - 1637564 \)
|
| $97$ |
\( T^{2} + 1096T + 98620 \)
|
| show more | |
| show less |