# Properties

 Label 256.5 Modulus $256$ Conductor $256$ Order $64$ Real no Primitive yes Minimal yes Parity even

# Related objects

Show commands for: Pari/GP / SageMath
sage: from sage.modular.dirichlet import DirichletCharacter

sage: H = DirichletGroup(256)

sage: M = H._module

sage: chi = DirichletCharacter(H, M([0,1]))

pari: [g,chi] = znchar(Mod(5,256))

## Basic properties

 Modulus: $$256$$ Conductor: $$256$$ sage: chi.conductor()  pari: znconreyconductor(g,chi) Order: $$64$$ 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 256.m

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

$$(255,5)$$ → $$(1,e\left(\frac{1}{64}\right))$$

## Values

 $$-1$$ $$1$$ $$3$$ $$5$$ $$7$$ $$9$$ $$11$$ $$13$$ $$15$$ $$17$$ $$19$$ $$21$$ $$1$$ $$1$$ $$e\left(\frac{35}{64}\right)$$ $$e\left(\frac{1}{64}\right)$$ $$e\left(\frac{5}{32}\right)$$ $$e\left(\frac{3}{32}\right)$$ $$e\left(\frac{21}{64}\right)$$ $$e\left(\frac{47}{64}\right)$$ $$e\left(\frac{9}{16}\right)$$ $$e\left(\frac{7}{16}\right)$$ $$e\left(\frac{23}{64}\right)$$ $$e\left(\frac{45}{64}\right)$$
 value at e.g. 2

## Related number fields

 Field of values: $\Q(\zeta_{64})$ Fixed field: Number field defined by a degree 64 polynomial

## Gauss sum

sage: chi.gauss_sum(a)

pari: znchargauss(g,chi,a)

$$\tau_{ a }( \chi_{ 256 }(5,·) )\;$$ at $$\;a =$$ e.g. 2
$$\displaystyle \tau_{2}(\chi_{256}(5,\cdot)) = \sum_{r\in \Z/256\Z} \chi_{256}(5,r) e\left(\frac{r}{128}\right) = -0.0$$

## Jacobi sum

sage: chi.jacobi_sum(n)

$$J(\chi_{ 256 }(5,·),\chi_{ 256 }(n,·)) \;$$ for $$\; n =$$ e.g. 1
$$\displaystyle J(\chi_{256}(5,\cdot),\chi_{256}(1,\cdot)) = \sum_{r\in \Z/256\Z} \chi_{256}(5,r) \chi_{256}(1,1-r) = 0$$

## Kloosterman sum

sage: chi.kloosterman_sum(a,b)

$$K(a,b,\chi_{ 256 }(5,·)) \;$$ at $$\; a,b =$$ e.g. 1,2
$$\displaystyle K(1,2,\chi_{256}(5,·)) = \sum_{r \in \Z/256\Z} \chi_{256}(5,r) e\left(\frac{1 r + 2 r^{-1}}{256}\right) = -12.1153415441+-10.4507654873i$$