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Properties

Label 18.2.54338589155...1648.2
Degree $18$
Signature $[2, 8]$
Discriminant $2^{24}\cdot 3^{33}\cdot 17^{12}$
Root discriminant $124.85$
Ramified primes $2, 3, 17$
Class number $9$ (GRH)
Class group $[9]$ (GRH)
Galois group $C_2\times He_3:C_2$ (as 18T41)

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![13824, 0, 0, 150336, 0, 0, -134460, 0, 0, 9612, 0, 0, 9774, 0, 0, -198, 0, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^18 - 198*x^15 + 9774*x^12 + 9612*x^9 - 134460*x^6 + 150336*x^3 + 13824)
 
gp: K = bnfinit(x^18 - 198*x^15 + 9774*x^12 + 9612*x^9 - 134460*x^6 + 150336*x^3 + 13824, 1)
 

Normalized defining polynomial

\( x^{18} - 198 x^{15} + 9774 x^{12} + 9612 x^{9} - 134460 x^{6} + 150336 x^{3} + 13824 \)

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:  \(54338589155044511351315661922026651648=2^{24}\cdot 3^{33}\cdot 17^{12}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $124.85$
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:  $2, 3, 17$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $\frac{1}{6} a^{6}$, $\frac{1}{6} a^{7}$, $\frac{1}{6} a^{8}$, $\frac{1}{90} a^{9} + \frac{1}{15} a^{6} + \frac{4}{15} a^{3} - \frac{1}{5}$, $\frac{1}{90} a^{10} + \frac{1}{15} a^{7} + \frac{4}{15} a^{4} - \frac{1}{5} a$, $\frac{1}{90} a^{11} + \frac{1}{15} a^{8} + \frac{4}{15} a^{5} - \frac{1}{5} a^{2}$, $\frac{1}{540} a^{12} - \frac{7}{90} a^{6} + \frac{1}{5} a^{3} - \frac{2}{15}$, $\frac{1}{1080} a^{13} - \frac{1}{180} a^{10} - \frac{13}{180} a^{7} - \frac{1}{30} a^{4} + \frac{1}{30} a$, $\frac{1}{2160} a^{14} - \frac{1}{360} a^{11} + \frac{17}{360} a^{8} - \frac{1}{60} a^{5} + \frac{1}{60} a^{2}$, $\frac{1}{8516504160} a^{15} - \frac{3997}{31542608} a^{12} + \frac{7001989}{1419417360} a^{9} - \frac{774221}{236569560} a^{6} + \frac{17048379}{78856520} a^{3} + \frac{4054673}{9857065}$, $\frac{1}{17033008320} a^{16} - \frac{3997}{63085216} a^{13} - \frac{584621}{189255648} a^{10} - \frac{1103035}{31542608} a^{7} + \frac{224629481}{473139120} a^{4} + \frac{3013043}{9857065} a$, $\frac{1}{34066016640} a^{17} - \frac{3997}{126170432} a^{14} + \frac{22773293}{5677669440} a^{11} - \frac{21286479}{315426080} a^{8} - \frac{122339207}{946278240} a^{5} + \frac{104163}{1971413} a^{2}$

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

Class group and class number

$C_{9}$, which has order $9$ (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:  \( 190737309233.46994 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$C_2\times He_3:C_2$ (as 18T41):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A solvable group of order 108
The 20 conjugacy class representatives for $C_2\times He_3:C_2$
Character table for $C_2\times He_3:C_2$

Intermediate fields

\(\Q(\sqrt{3}) \), 3.1.867.1, 6.2.144324288.1, 9.1.66498764695119936.21

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

Sibling fields

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 ${\href{/LocalNumberField/5.6.0.1}{6} }^{2}{,}\,{\href{/LocalNumberField/5.2.0.1}{2} }^{3}$ ${\href{/LocalNumberField/7.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/11.6.0.1}{6} }^{2}{,}\,{\href{/LocalNumberField/11.2.0.1}{2} }^{2}{,}\,{\href{/LocalNumberField/11.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/13.3.0.1}{3} }^{6}$ R ${\href{/LocalNumberField/19.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/23.6.0.1}{6} }^{2}{,}\,{\href{/LocalNumberField/23.2.0.1}{2} }^{2}{,}\,{\href{/LocalNumberField/23.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/29.6.0.1}{6} }^{2}{,}\,{\href{/LocalNumberField/29.2.0.1}{2} }^{3}$ ${\href{/LocalNumberField/31.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/37.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/41.6.0.1}{6} }^{2}{,}\,{\href{/LocalNumberField/41.2.0.1}{2} }^{3}$ ${\href{/LocalNumberField/43.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/47.6.0.1}{6} }^{2}{,}\,{\href{/LocalNumberField/47.2.0.1}{2} }^{2}{,}\,{\href{/LocalNumberField/47.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/53.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/59.6.0.1}{6} }^{2}{,}\,{\href{/LocalNumberField/59.2.0.1}{2} }^{2}{,}\,{\href{/LocalNumberField/59.1.0.1}{1} }^{2}$

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$2.6.8.3$x^{6} + 2 x^{3} + 6$$6$$1$$8$$D_{6}$$[2]_{3}^{2}$
2.12.16.3$x^{12} - 30 x^{10} - 5 x^{8} + 19 x^{4} + 30 x^{2} + 1$$6$$2$$16$$C_6\times S_3$$[2]_{3}^{6}$
$3$3.6.11.3$x^{6} + 6$$6$$1$$11$$D_{6}$$[5/2]_{2}^{2}$
3.12.22.93$x^{12} + 81 x^{11} - 81 x^{10} + 51 x^{9} + 63 x^{8} - 108 x^{7} - 93 x^{6} + 108 x^{5} + 72 x^{3} + 108 x^{2} - 81 x + 90$$6$$2$$22$$C_6\times S_3$$[2, 5/2]_{2}^{2}$
$17$17.6.4.1$x^{6} + 136 x^{3} + 7803$$3$$2$$4$$S_3$$[\ ]_{3}^{2}$
17.6.4.1$x^{6} + 136 x^{3} + 7803$$3$$2$$4$$S_3$$[\ ]_{3}^{2}$
17.6.4.1$x^{6} + 136 x^{3} + 7803$$3$$2$$4$$S_3$$[\ ]_{3}^{2}$