Properties

Label 8.0.513366837760000.109
Degree $8$
Signature $[0, 4]$
Discriminant $2^{12}\cdot 5^{4}\cdot 7^{4}\cdot 17^{4}$
Root discriminant $68.99$
Ramified primes $2, 5, 7, 17$
Class number $1600$ (GRH)
Class group $[4, 20, 20]$ (GRH)
Galois group $C_2^3$ (as 8T3)

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![1164241, 0, 119134, 0, 4967, 0, 106, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^8 + 106*x^6 + 4967*x^4 + 119134*x^2 + 1164241)
 
gp: K = bnfinit(x^8 + 106*x^6 + 4967*x^4 + 119134*x^2 + 1164241, 1)
 

Normalized defining polynomial

\( x^{8} + 106 x^{6} + 4967 x^{4} + 119134 x^{2} + 1164241 \)

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:  \(513366837760000=2^{12}\cdot 5^{4}\cdot 7^{4}\cdot 17^{4}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $68.99$
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:  $2, 5, 7, 17$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is Galois and abelian over $\Q$.
Conductor:  \(4760=2^{3}\cdot 5\cdot 7\cdot 17\)
Dirichlet character group:    $\lbrace$$\chi_{4760}(1,·)$, $\chi_{4760}(1189,·)$, $\chi_{4760}(3809,·)$, $\chi_{4760}(4521,·)$, $\chi_{4760}(2381,·)$, $\chi_{4760}(3569,·)$, $\chi_{4760}(1429,·)$, $\chi_{4760}(2141,·)$$\rbrace$
This is a CM field.

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

$1$, $a$, $a^{2}$, $a^{3}$, $\frac{1}{4} a^{4} - \frac{1}{2} a^{3} - \frac{1}{4} a^{2} - \frac{1}{2} a - \frac{1}{4}$, $\frac{1}{4} a^{5} - \frac{1}{4} a^{3} - \frac{1}{4} a - \frac{1}{2}$, $\frac{1}{47244} a^{6} + \frac{1019}{11811} a^{4} - \frac{1}{2} a^{3} - \frac{3097}{23622} a^{2} - \frac{10465}{47244}$, $\frac{1}{50976276} a^{7} - \frac{565909}{12744069} a^{5} - \frac{6522769}{25488138} a^{3} - \frac{1}{2} a^{2} + \frac{16005251}{50976276} a - \frac{1}{2}$

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

Class group and class number

$C_{4}\times C_{20}\times C_{20}$, which has order $1600$ (assuming GRH)

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:  \( \frac{17}{200694} a^{7} + \frac{2525}{401388} a^{5} + \frac{85795}{401388} a^{3} + \frac{1200917}{401388} a - \frac{1}{2} \),  \( \frac{77}{822198} a^{7} + \frac{3002}{411099} a^{5} + \frac{109765}{411099} a^{3} + \frac{3218317}{822198} a - 1 \),  \( \frac{38}{4248023} a^{7} + \frac{17191}{16992092} a^{5} + \frac{904965}{16992092} a^{3} + \frac{15673065}{16992092} a - \frac{1}{2} \) (assuming GRH)
magma: [K!f(g): g in Generators(UK)];
 
sage: UK.fundamental_units()
 
gp: K.fu
 
Regulator:  \( 12.3400472787 \) (assuming GRH)
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

\(\Q(\sqrt{-238}) \), \(\Q(\sqrt{5}) \), \(\Q(\sqrt{-1190}) \), \(\Q(\sqrt{2}) \), \(\Q(\sqrt{-119}) \), \(\Q(\sqrt{10}) \), \(\Q(\sqrt{-595}) \), \(\Q(\sqrt{5}, \sqrt{-238})\), \(\Q(\sqrt{2}, \sqrt{-119})\), \(\Q(\sqrt{10}, \sqrt{-238})\), \(\Q(\sqrt{2}, \sqrt{5})\), \(\Q(\sqrt{5}, \sqrt{-119})\), \(\Q(\sqrt{2}, \sqrt{-595})\), \(\Q(\sqrt{10}, \sqrt{-119})\)

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 ${\href{/LocalNumberField/3.2.0.1}{2} }^{4}$ R R ${\href{/LocalNumberField/11.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/13.2.0.1}{2} }^{4}$ R ${\href{/LocalNumberField/19.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/23.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/29.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/31.1.0.1}{1} }^{8}$ ${\href{/LocalNumberField/37.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/41.1.0.1}{1} }^{8}$ ${\href{/LocalNumberField/43.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/47.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/53.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/59.2.0.1}{2} }^{4}$

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$2.4.6.1$x^{4} - 6 x^{2} + 4$$2$$2$$6$$C_2^2$$[3]^{2}$
2.4.6.1$x^{4} - 6 x^{2} + 4$$2$$2$$6$$C_2^2$$[3]^{2}$
$5$5.4.2.1$x^{4} + 15 x^{2} + 100$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
5.4.2.1$x^{4} + 15 x^{2} + 100$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
$7$7.4.2.1$x^{4} + 35 x^{2} + 441$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
7.4.2.1$x^{4} + 35 x^{2} + 441$$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}$