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Properties

Label 18.2.10623530180...6448.1
Degree $18$
Signature $[2, 8]$
Discriminant $2^{18}\cdot 3^{39}$
Root discriminant $21.62$
Ramified primes $2, 3$
Class number $1$ (GRH)
Class group Trivial (GRH)
Galois group $S_3^2$ (as 18T9)

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![-8, 0, 0, 12, 0, 0, -39, 0, 0, -38, 0, 0, -30, 0, 0, -6, 0, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^18 - 6*x^15 - 30*x^12 - 38*x^9 - 39*x^6 + 12*x^3 - 8)
 
gp: K = bnfinit(x^18 - 6*x^15 - 30*x^12 - 38*x^9 - 39*x^6 + 12*x^3 - 8, 1)
 

Normalized defining polynomial

\( x^{18} - 6 x^{15} - 30 x^{12} - 38 x^{9} - 39 x^{6} + 12 x^{3} - 8 \)

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

Invariants

Degree:  $18$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[2, 8]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(1062353018033006514536448=2^{18}\cdot 3^{39}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $21.62$
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:  $2, 3$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is not Galois over $\Q$.
This is not a CM field.

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

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $\frac{1}{3} a^{6} + \frac{1}{3} a^{3} + \frac{1}{3}$, $\frac{1}{3} a^{7} + \frac{1}{3} a^{4} + \frac{1}{3} a$, $\frac{1}{6} a^{8} - \frac{1}{3} a^{5} + \frac{1}{6} a^{2}$, $\frac{1}{6} a^{9} - \frac{1}{2} a^{3} + \frac{1}{3}$, $\frac{1}{6} a^{10} - \frac{1}{2} a^{4} + \frac{1}{3} a$, $\frac{1}{18} a^{11} + \frac{1}{18} a^{10} + \frac{1}{18} a^{9} + \frac{1}{6} a^{5} + \frac{1}{6} a^{4} + \frac{1}{6} a^{3} - \frac{2}{9} a^{2} - \frac{2}{9} a - \frac{2}{9}$, $\frac{1}{18} a^{12} - \frac{1}{18} a^{9} - \frac{1}{6} a^{6} + \frac{5}{18} a^{3} - \frac{1}{9}$, $\frac{1}{18} a^{13} - \frac{1}{18} a^{10} - \frac{1}{6} a^{7} + \frac{5}{18} a^{4} - \frac{1}{9} a$, $\frac{1}{18} a^{14} + \frac{1}{18} a^{10} + \frac{1}{18} a^{9} + \frac{1}{9} a^{5} + \frac{1}{6} a^{4} + \frac{1}{6} a^{3} - \frac{1}{6} a^{2} - \frac{2}{9} a - \frac{2}{9}$, $\frac{1}{126} a^{15} - \frac{1}{42} a^{12} - \frac{2}{63} a^{9} - \frac{1}{126} a^{6} + \frac{1}{6} a^{3} + \frac{20}{63}$, $\frac{1}{756} a^{16} + \frac{1}{378} a^{15} + \frac{1}{189} a^{13} + \frac{2}{189} a^{12} - \frac{8}{189} a^{10} + \frac{31}{378} a^{9} - \frac{16}{189} a^{7} + \frac{31}{189} a^{6} - \frac{43}{108} a^{4} + \frac{1}{27} a^{3} + \frac{17}{189} a - \frac{29}{189}$, $\frac{1}{756} a^{17} + \frac{1}{378} a^{15} + \frac{1}{189} a^{14} + \frac{2}{189} a^{12} + \frac{5}{378} a^{11} + \frac{1}{18} a^{10} - \frac{11}{378} a^{9} + \frac{31}{378} a^{8} + \frac{31}{189} a^{6} + \frac{47}{108} a^{5} + \frac{1}{6} a^{4} - \frac{8}{27} a^{3} + \frac{13}{378} a^{2} - \frac{2}{9} a + \frac{55}{189}$

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

Class group and class number

Trivial group, which has order $1$ (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:  $9$
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:  Units are too long to display, but can be downloaded with other data for this field from 'Stored data to gp' link to the right (assuming GRH)
magma: [K!f(g): g in Generators(UK)];
 
sage: UK.fundamental_units()
 
gp: K.fu
 
Regulator:  \( 347771.6804289576 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$S_3^2$ (as 18T9):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A solvable group of order 36
The 9 conjugacy class representatives for $S_3^2$
Character table for $S_3^2$

Intermediate fields

\(\Q(\sqrt{3}) \), 3.1.324.1, 3.1.243.1, 6.2.11337408.3 x2, 6.2.1259712.2, 6.2.11337408.2, 9.1.74384733888.1

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

Sibling fields

Galois closure: data not computed
Degree 6 sibling: data not computed
Degree 9 sibling: data not computed
Degree 12 sibling: data not computed
Degree 18 siblings: data not computed

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 ${\href{/LocalNumberField/5.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/7.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/11.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/11.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/13.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/17.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/19.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/23.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/23.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/29.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/31.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/37.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/41.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/43.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/47.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/47.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/53.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/59.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/59.1.0.1}{1} }^{2}$

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$$[2]$
2.4.4.1$x^{4} + 8 x^{2} + 4$$2$$2$$4$$C_2^2$$[2]^{2}$
2.4.4.1$x^{4} + 8 x^{2} + 4$$2$$2$$4$$C_2^2$$[2]^{2}$
2.4.4.1$x^{4} + 8 x^{2} + 4$$2$$2$$4$$C_2^2$$[2]^{2}$
2.4.4.1$x^{4} + 8 x^{2} + 4$$2$$2$$4$$C_2^2$$[2]^{2}$
3Data not computed