Properties

Label 8.0.484654236938496.8
Degree $8$
Signature $[0, 4]$
Discriminant $2^{8}\cdot 3^{4}\cdot 17^{4}\cdot 23^{4}$
Root discriminant $68.50$
Ramified primes $2, 3, 17, 23$
Class number $1008$
Class group $[2, 6, 84]$
Galois group $C_2^3$ (as 8T3)

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magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![13924, 0, 3984, 0, 245, 0, -6, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^8 - 6*x^6 + 245*x^4 + 3984*x^2 + 13924)
 
gp: K = bnfinit(x^8 - 6*x^6 + 245*x^4 + 3984*x^2 + 13924, 1)
 

Normalized defining polynomial

\( x^{8} - 6 x^{6} + 245 x^{4} + 3984 x^{2} + 13924 \)

magma: DefiningPolynomial(K);
 
sage: K.defining_polynomial()
 
gp: K.pol
 

Invariants

Degree:  $8$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[0, 4]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(484654236938496=2^{8}\cdot 3^{4}\cdot 17^{4}\cdot 23^{4}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $68.50$
magma: Abs(Discriminant(Integers(K)))^(1/Degree(K));
 
sage: (K.disc().abs())^(1./K.degree())
 
gp: abs(K.disc)^(1/poldegree(K.pol))
 
Ramified primes:  $2, 3, 17, 23$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is Galois and abelian over $\Q$.
Conductor:  \(4692=2^{2}\cdot 3\cdot 17\cdot 23\)
Dirichlet character group:    $\lbrace$$\chi_{4692}(2209,·)$, $\chi_{4692}(1,·)$, $\chi_{4692}(3265,·)$, $\chi_{4692}(3911,·)$, $\chi_{4692}(1427,·)$, $\chi_{4692}(781,·)$, $\chi_{4692}(4691,·)$, $\chi_{4692}(2483,·)$$\rbrace$
This is a CM field.

Integral basis (with respect to field generator \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $\frac{1}{20} a^{4} - \frac{1}{2} a^{3} - \frac{1}{4} a^{2} - \frac{1}{2} a + \frac{3}{10}$, $\frac{1}{40} a^{5} - \frac{1}{8} a^{3} - \frac{7}{20} a - \frac{1}{2}$, $\frac{1}{1400} a^{6} + \frac{1}{200} a^{4} + \frac{49}{100} a^{2} - \frac{1}{2} a - \frac{6}{175}$, $\frac{1}{82600} a^{7} + \frac{2}{1475} a^{5} - \frac{3977}{11800} a^{3} - \frac{1}{2} a^{2} - \frac{9159}{41300} a - \frac{1}{2}$

magma: IntegralBasis(K);
 
sage: K.integral_basis()
 
gp: K.zk
 

Class group and class number

$C_{2}\times C_{6}\times C_{84}$, which has order $1008$

magma: ClassGroup(K);
 
sage: K.class_group().invariants()
 
gp: K.clgp
 

Unit group

magma: UK, f := UnitGroup(K);
 
sage: UK = K.unit_group()
 
Rank:  $3$
magma: UnitRank(K);
 
sage: UK.rank()
 
gp: K.fu
 
Torsion generator:  \( -1 \) (order $2$)
magma: K!f(TU.1) where TU,f is TorsionUnitGroup(K);
 
sage: UK.torsion_generator()
 
gp: K.tu[2]
 
Fundamental units:  \( \frac{33}{41300} a^{7} - \frac{31}{2950} a^{5} + \frac{1509}{5900} a^{3} + \frac{36413}{20650} a + 2 \),  \( \frac{3}{1475} a^{7} - \frac{131}{5900} a^{5} + \frac{3707}{5900} a^{3} + \frac{12517}{2950} a + 4 \),  \( \frac{69}{11800} a^{7} - \frac{1}{1400} a^{6} - \frac{827}{11800} a^{5} - \frac{1}{200} a^{4} + \frac{5421}{2950} a^{3} + \frac{1}{100} a^{2} + \frac{18491}{1475} a - \frac{1219}{175} \)
magma: [K!f(g): g in Generators(UK)];
 
sage: UK.fundamental_units()
 
gp: K.fu
 
Regulator:  \( 203.260298886 \)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$C_2^3$ (as 8T3):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
An abelian group of order 8
The 8 conjugacy class representatives for $C_2^3$
Character table for $C_2^3$

Intermediate fields

\(\Q(\sqrt{-1173}) \), \(\Q(\sqrt{-23}) \), \(\Q(\sqrt{51}) \), \(\Q(\sqrt{17}) \), \(\Q(\sqrt{-69}) \), \(\Q(\sqrt{-391}) \), \(\Q(\sqrt{3}) \), \(\Q(\sqrt{-23}, \sqrt{51})\), \(\Q(\sqrt{17}, \sqrt{-69})\), \(\Q(\sqrt{3}, \sqrt{-391})\), \(\Q(\sqrt{17}, \sqrt{-23})\), \(\Q(\sqrt{3}, \sqrt{-23})\), \(\Q(\sqrt{3}, \sqrt{17})\), \(\Q(\sqrt{51}, \sqrt{-69})\)

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

Frobenius cycle types

$p$ 2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59
Cycle type R R ${\href{/LocalNumberField/5.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/7.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/11.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/13.1.0.1}{1} }^{8}$ R ${\href{/LocalNumberField/19.2.0.1}{2} }^{4}$ R ${\href{/LocalNumberField/29.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/31.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/37.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/41.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/43.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/47.1.0.1}{1} }^{8}$ ${\href{/LocalNumberField/53.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/59.1.0.1}{1} }^{8}$

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

magma: p := 7; // to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$:
 
magma: idealfactors := Factorization(p*Integers(K)); // get the data
 
magma: [<primefactor[2], Valuation(Norm(primefactor[1]), p)> : primefactor in idealfactors];
 
sage: p = 7; # to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$:
 
sage: [(e, pr.norm().valuation(p)) for pr,e in K.factor(p)]
 
gp: p = 7; \\ to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$:
 
gp: idealfactors = idealprimedec(K, p); \\ get the data
 
gp: vector(length(idealfactors), j, [idealfactors[j][3], idealfactors[j][4]])
 

Local algebras for ramified primes

$p$LabelPolynomial $e$ $f$ $c$ Galois group Slope content
$2$2.2.2.2$x^{2} + 2 x - 2$$2$$1$$2$$C_2$$[2]$
2.2.2.2$x^{2} + 2 x - 2$$2$$1$$2$$C_2$$[2]$
2.2.2.2$x^{2} + 2 x - 2$$2$$1$$2$$C_2$$[2]$
2.2.2.2$x^{2} + 2 x - 2$$2$$1$$2$$C_2$$[2]$
$3$3.4.2.1$x^{4} + 9 x^{2} + 36$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
3.4.2.1$x^{4} + 9 x^{2} + 36$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
$17$17.4.2.1$x^{4} + 85 x^{2} + 2601$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
17.4.2.1$x^{4} + 85 x^{2} + 2601$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
$23$23.4.2.1$x^{4} + 299 x^{2} + 25921$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
23.4.2.1$x^{4} + 299 x^{2} + 25921$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$