# Properties

 Label 8.0.1601613.1 Degree $8$ Signature $[0, 4]$ Discriminant $1601613$ Root discriminant $$5.96$$ Ramified primes $3,13$ Class number $1$ Class group trivial Galois group $C_4\wr C_2$ (as 8T17)

# Related objects

Show commands: Magma / Oscar / PariGP / SageMath

## Normalizeddefining polynomial

sage: x = polygen(QQ); K.<a> = NumberField(x^8 - 2*x^6 - 3*x^5 + 3*x^4 + 3*x^3 - 2*x^2 + 1)

gp: K = bnfinit(y^8 - 2*y^6 - 3*y^5 + 3*y^4 + 3*y^3 - 2*y^2 + 1, 1)

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^8 - 2*x^6 - 3*x^5 + 3*x^4 + 3*x^3 - 2*x^2 + 1);

oscar: Qx, x = PolynomialRing(QQ); K, a = NumberField(x^8 - 2*x^6 - 3*x^5 + 3*x^4 + 3*x^3 - 2*x^2 + 1)

$$x^{8} - 2x^{6} - 3x^{5} + 3x^{4} + 3x^{3} - 2x^{2} + 1$$

sage: K.defining_polynomial()

gp: K.pol

magma: DefiningPolynomial(K);

oscar: defining_polynomial(K)

## Invariants

 Degree: $8$ sage: K.degree()  gp: poldegree(K.pol)  magma: Degree(K);  oscar: degree(K) Signature: $[0, 4]$ sage: K.signature()  gp: K.sign  magma: Signature(K);  oscar: signature(K) Discriminant: $$1601613$$ 1601613 $$\medspace = 3^{6}\cdot 13^{3}$$ sage: K.disc()  gp: K.disc  magma: OK := Integers(K); Discriminant(OK);  oscar: OK = ring_of_integers(K); discriminant(OK) Root discriminant: $$5.96$$ sage: (K.disc().abs())^(1./K.degree())  gp: abs(K.disc)^(1/poldegree(K.pol))  magma: Abs(Discriminant(OK))^(1/Degree(K));  oscar: (1.0 * dK)^(1/degree(K)) Galois root discriminant: $3^{3/4}13^{3/4}\approx 15.606246247497747$ Ramified primes: $$3$$, $$13$$ 3, 13 sage: K.disc().support()  gp: factor(abs(K.disc))[,1]~  magma: PrimeDivisors(Discriminant(OK));  oscar: prime_divisors(discriminant((OK))) Discriminant root field: $$\Q(\sqrt{13})$$ $\card{ \Aut(K/\Q) }$: $4$ sage: K.automorphisms()  magma: Automorphisms(K);  oscar: automorphisms(K) This field is not Galois over $\Q$. This is not a CM field.

## Integral basis (with respect to field generator $$a$$)

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$

sage: K.integral_basis()

gp: K.zk

magma: IntegralBasis(K);

oscar: basis(OK)

 Monogenic: Yes Index: $1$ Inessential primes: None

## Class group and class number

Trivial group, which has order $1$

sage: K.class_group().invariants()

gp: K.clgp

magma: ClassGroup(K);

oscar: class_group(K)

## Unit group

sage: UK = K.unit_group()

magma: UK, fUK := UnitGroup(K);

oscar: UK, fUK = unit_group(OK)

 Rank: $3$ sage: UK.rank()  gp: K.fu  magma: UnitRank(K);  oscar: rank(UK) Torsion generator: $$3 a^{7} - a^{6} - 4 a^{5} - 7 a^{4} + 10 a^{3} + a^{2} - 4 a + 3$$ 3*a^(7) - a^(6) - 4*a^(5) - 7*a^(4) + 10*a^(3) + a^(2) - 4*a + 3  (order $6$) sage: UK.torsion_generator()  gp: K.tu[2]  magma: K!f(TU.1) where TU,f is TorsionUnitGroup(K);  oscar: torsion_units_generator(OK) Fundamental units: $a^{7}-a^{5}-3a^{4}+2a^{3}+1$, $2a^{7}-a^{6}-3a^{5}-5a^{4}+7a^{3}+a^{2}-2a+2$, $a^{7}-2a^{6}-2a^{5}-a^{4}+8a^{3}-2a^{2}-3a+3$ a^7 - a^5 - 3*a^4 + 2*a^3 + 1, 2*a^7 - a^6 - 3*a^5 - 5*a^4 + 7*a^3 + a^2 - 2*a + 2, a^7 - 2*a^6 - 2*a^5 - a^4 + 8*a^3 - 2*a^2 - 3*a + 3 sage: UK.fundamental_units()  gp: K.fu  magma: [K|fUK(g): g in Generators(UK)];  oscar: [K(fUK(a)) for a in gens(UK)] Regulator: $$1.10095849199$$ sage: K.regulator()  gp: K.reg  magma: Regulator(K);  oscar: regulator(K)

## Class number formula

\begin{aligned}\lim_{s\to 1} (s-1)\zeta_K(s) =\mathstrut & \frac{2^{r_1}\cdot (2\pi)^{r_2}\cdot R\cdot h}{w\cdot\sqrt{|D|}}\cr \approx\mathstrut &\frac{2^{0}\cdot(2\pi)^{4}\cdot 1.10095849199 \cdot 1}{6\cdot\sqrt{1601613}}\cr\approx \mathstrut & 0.225974990116 \end{aligned}

# self-contained SageMath code snippet to compute the analytic class number formula

x = polygen(QQ); K.<a> = NumberField(x^8 - 2*x^6 - 3*x^5 + 3*x^4 + 3*x^3 - 2*x^2 + 1)

DK = K.disc(); r1,r2 = K.signature(); RK = K.regulator(); RR = RK.parent()

hK = K.class_number(); wK = K.unit_group().torsion_generator().order();

2^r1 * (2*RR(pi))^r2 * RK * hK / (wK * RR(sqrt(abs(DK))))

# self-contained Pari/GP code snippet to compute the analytic class number formula

K = bnfinit(x^8 - 2*x^6 - 3*x^5 + 3*x^4 + 3*x^3 - 2*x^2 + 1, 1);

[polcoeff (lfunrootres (lfuncreate (K))[1][1][2], -1), 2^K.r1 * (2*Pi)^K.r2 * K.reg * K.no / (K.tu[1] * sqrt (abs (K.disc)))]

/* self-contained Magma code snippet to compute the analytic class number formula */

Qx<x> := PolynomialRing(QQ); K<a> := NumberField(x^8 - 2*x^6 - 3*x^5 + 3*x^4 + 3*x^3 - 2*x^2 + 1);

OK := Integers(K); DK := Discriminant(OK);

UK, fUK := UnitGroup(OK); clK, fclK := ClassGroup(OK);

r1,r2 := Signature(K); RK := Regulator(K); RR := Parent(RK);

hK := #clK; wK := #TorsionSubgroup(UK);

2^r1 * (2*Pi(RR))^r2 * RK * hK / (wK * Sqrt(RR!Abs(DK)));

# self-contained Oscar code snippet to compute the analytic class number formula

Qx, x = PolynomialRing(QQ); K, a = NumberField(x^8 - 2*x^6 - 3*x^5 + 3*x^4 + 3*x^3 - 2*x^2 + 1);

OK = ring_of_integers(K); DK = discriminant(OK);

UK, fUK = unit_group(OK); clK, fclK = class_group(OK);

r1,r2 = signature(K); RK = regulator(K); RR = parent(RK);

hK = order(clK); wK = torsion_units_order(K);

2^r1 * (2*pi)^r2 * RK * hK / (wK * sqrt(RR(abs(DK))))

## Galois group

$C_4\wr C_2$ (as 8T17):

sage: K.galois_group(type='pari')

gp: polgalois(K.pol)

magma: G = GaloisGroup(K);

oscar: G, Gtx = galois_group(K); G, transitive_group_identification(G)

 A solvable group of order 32 The 14 conjugacy class representatives for $C_4\wr C_2$ Character table for $C_4\wr C_2$

## Intermediate fields

Fields in the database are given up to isomorphism. Isomorphic intermediate fields are shown with their multiplicities.

sage: K.subfields()[1:-1]

gp: L = nfsubfields(K); L[2..length(b)]

magma: L := Subfields(K); L[2..#L];

oscar: subfields(K)[2:end-1]

## Sibling fields

 Galois closure: data not computed Degree 8 sibling: data not computed Degree 16 siblings: 16.4.12381557655576425121.1, 16.0.73263654766724409.1 Minimal sibling: This field is its own minimal sibling

## Frobenius cycle types

 $p$ $2$ $3$ $5$ $7$ $11$ $13$ $17$ $19$ $23$ $29$ $31$ $37$ $41$ $43$ $47$ $53$ $59$ Cycle type ${\href{/padicField/2.8.0.1}{8} }$ R ${\href{/padicField/5.8.0.1}{8} }$ ${\href{/padicField/7.4.0.1}{4} }{,}\,{\href{/padicField/7.2.0.1}{2} }^{2}$ ${\href{/padicField/11.8.0.1}{8} }$ R ${\href{/padicField/17.2.0.1}{2} }^{4}$ ${\href{/padicField/19.4.0.1}{4} }{,}\,{\href{/padicField/19.2.0.1}{2} }^{2}$ ${\href{/padicField/23.2.0.1}{2} }^{4}$ ${\href{/padicField/29.4.0.1}{4} }^{2}$ ${\href{/padicField/31.4.0.1}{4} }{,}\,{\href{/padicField/31.1.0.1}{1} }^{4}$ ${\href{/padicField/37.4.0.1}{4} }{,}\,{\href{/padicField/37.1.0.1}{1} }^{4}$ ${\href{/padicField/41.8.0.1}{8} }$ ${\href{/padicField/43.2.0.1}{2} }^{2}{,}\,{\href{/padicField/43.1.0.1}{1} }^{4}$ ${\href{/padicField/47.8.0.1}{8} }$ ${\href{/padicField/53.4.0.1}{4} }^{2}$ ${\href{/padicField/59.8.0.1}{8} }$

In the table, R denotes a ramified prime. Cycle lengths which are repeated in a cycle type are indicated by exponents.

# to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$ for $p=7$ in Sage:

p = 7; [(e, pr.norm().valuation(p)) for pr,e in K.factor(p)]

\\ to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$ for $p=7$ in Pari:

p = 7; pfac = idealprimedec(K, p); vector(length(pfac), j, [pfac[j][3], pfac[j][4]])

// to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$ for $p=7 in Magma: p := 7; [<pr[2], Valuation(Norm(pr[1]), p)> : pr in Factorization(p*Integers(K))]; # to obtain a list of$[e_i,f_i]$for the factorization of the ideal$p\mathcal{O}_K$for$p=7$in Oscar: p = 7; pfac = factor(ideal(ring_of_integers(K), p)); [(e, valuation(norm(pr),p)) for (pr,e) in pfac] ## Local algebras for ramified primes$p$LabelPolynomial$efc$Galois group Slope content $$3$$ 3.8.6.1$x^{8} + 9$$4$$2$$6$$Q_8$$[\ ]_{4}^{2} $$13$$ 13.4.3.4x^{4} + 91$$4$$1$$3$$C_4$$[\ ]_{4}$13.4.0.1$x^{4} + 3 x^{2} + 12 x + 2$$1$$4$$0$$C_4[\ ]^{4}$## Artin representations Label Dimension Conductor Artin stem field$G$Ind$\chi(c)$* 1.1.1t1.a.a$11$$$\Q$$$C_111$1.13.2t1.a.a$1 13 $$$\Q(\sqrt{13})$$$C_2$(as 2T1)$11$1.39.2t1.a.a$1 3 \cdot 13 $$$\Q(\sqrt{-39})$$$C_2$(as 2T1)$1-1$* 1.3.2t1.a.a$1 3 $$$\Q(\sqrt{-3})$$$C_2$(as 2T1)$1-1$1.39.4t1.a.a$1 3 \cdot 13 $4.4.19773.1$C_4$(as 4T1)$01$1.39.4t1.a.b$1 3 \cdot 13 $4.4.19773.1$C_4$(as 4T1)$01$1.13.4t1.a.a$1 13 $4.0.2197.1$C_4$(as 4T1)$0-1$1.13.4t1.a.b$1 13 $4.0.2197.1$C_4$(as 4T1)$0-1$2.507.4t3.c.a$2 3 \cdot 13^{2}$4.0.19773.1$D_{4}$(as 4T3)$10$* 2.39.4t3.a.a$2 3 \cdot 13 $4.0.117.1$D_{4}$(as 4T3)$10$* 2.117.8t17.b.a$2 3^{2} \cdot 13 $8.0.1601613.1$C_4\wr C_2$(as 8T17)$00$2.1521.8t17.b.a$2 3^{2} \cdot 13^{2}$8.0.1601613.1$C_4\wr C_2$(as 8T17)$00$* 2.117.8t17.b.b$2 3^{2} \cdot 13 $8.0.1601613.1$C_4\wr C_2$(as 8T17)$00$2.1521.8t17.b.b$2 3^{2} \cdot 13^{2}$8.0.1601613.1$C_4\wr C_2$(as 8T17)$00\$

Data is given for all irreducible representations of the Galois group for the Galois closure of this field. Those marked with * are summands in the permutation representation coming from this field. Representations which appear with multiplicity greater than one are indicated by exponents on the *.