sage: from sage.modular.dirichlet import DirichletCharacter
sage: H = DirichletGroup(20, base_ring=CyclotomicField(4))
sage: M = H._module
sage: chi = DirichletCharacter(H, M([2,1]))
pari: [g,chi] = znchar(Mod(7,20))
Basic properties
Modulus: | \(20\) | |
Conductor: | \(20\) | sage: chi.conductor()
pari: znconreyconductor(g,chi)
|
Order: | \(4\) | sage: chi.multiplicative_order()
pari: charorder(g,chi)
|
Real: | no | |
Primitive: | yes | sage: chi.is_primitive()
pari: #znconreyconductor(g,chi)==1
|
Minimal: | yes | |
Parity: | even | sage: chi.is_odd()
pari: zncharisodd(g,chi)
|
Galois orbit 20.e
\(\chi_{20}(3,\cdot)\) \(\chi_{20}(7,\cdot)\)
sage: chi.galois_orbit()
pari: order = charorder(g,chi)
pari: [ charpow(g,chi, k % order) | k <-[1..order-1], gcd(k,order)==1 ]
Values on generators
\((11,17)\) → \((-1,i)\)
Values
\(-1\) | \(1\) | \(3\) | \(7\) | \(9\) | \(11\) | \(13\) | \(17\) |
\(1\) | \(1\) | \(i\) | \(-i\) | \(-1\) | \(-1\) | \(-i\) | \(i\) |
Related number fields
Field of values: | \(\Q(\sqrt{-1}) \) |
Fixed field: | \(\Q(\zeta_{20})^+\) |
Gauss sum
sage: chi.gauss_sum(a)
pari: znchargauss(g,chi,a)
\(\displaystyle \tau_{2}(\chi_{20}(7,\cdot)) = \sum_{r\in \Z/20\Z} \chi_{20}(7,r) e\left(\frac{r}{10}\right) = 0.0 \)
Jacobi sum
sage: chi.jacobi_sum(n)
\( \displaystyle J(\chi_{20}(7,\cdot),\chi_{20}(1,\cdot)) = \sum_{r\in \Z/20\Z} \chi_{20}(7,r) \chi_{20}(1,1-r) = 0 \)
Kloosterman sum
sage: chi.kloosterman_sum(a,b)
\( \displaystyle K(1,2,\chi_{20}(7,·))
= \sum_{r \in \Z/20\Z}
\chi_{20}(7,r) e\left(\frac{1 r + 2 r^{-1}}{20}\right)
= 2.3511410092+2.3511410092i \)