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Properties

Label 18.0.18359346236...7136.1
Degree $18$
Signature $[0, 9]$
Discriminant $-\,2^{24}\cdot 3^{20}\cdot 11^{12}$
Root discriminant $42.24$
Ramified primes $2, 3, 11$
Class number $18$ (GRH)
Class group $[3, 6]$ (GRH)
Galois group $C_2\times C_3:S_3$ (as 18T12)

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![4096, 0, -5376, 0, -4752, 0, 2769, 0, 3849, 0, 1482, 0, 177, 0, -18, 0, -3, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^18 - 3*x^16 - 18*x^14 + 177*x^12 + 1482*x^10 + 3849*x^8 + 2769*x^6 - 4752*x^4 - 5376*x^2 + 4096)
 
gp: K = bnfinit(x^18 - 3*x^16 - 18*x^14 + 177*x^12 + 1482*x^10 + 3849*x^8 + 2769*x^6 - 4752*x^4 - 5376*x^2 + 4096, 1)
 

Normalized defining polynomial

\( x^{18} - 3 x^{16} - 18 x^{14} + 177 x^{12} + 1482 x^{10} + 3849 x^{8} + 2769 x^{6} - 4752 x^{4} - 5376 x^{2} + 4096 \)

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

Invariants

Degree:  $18$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[0, 9]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(-183593462369306069451078107136=-\,2^{24}\cdot 3^{20}\cdot 11^{12}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $42.24$
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:  $2, 3, 11$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $\frac{1}{2} a^{7} - \frac{1}{2} a^{6} - \frac{1}{2} a^{4} - \frac{1}{2} a^{2} - \frac{1}{2} a$, $\frac{1}{2} a^{8} - \frac{1}{2} a^{6} - \frac{1}{2} a^{5} - \frac{1}{2} a^{4} - \frac{1}{2} a^{3} - \frac{1}{2} a$, $\frac{1}{2} a^{9} - \frac{1}{2} a^{5} - \frac{1}{2} a$, $\frac{1}{2} a^{10} - \frac{1}{2} a^{6} - \frac{1}{2} a^{2}$, $\frac{1}{2} a^{11} - \frac{1}{2} a^{6} - \frac{1}{2} a^{4} - \frac{1}{2} a^{3} - \frac{1}{2} a^{2} - \frac{1}{2} a$, $\frac{1}{6} a^{12} - \frac{1}{6} a^{6} - \frac{1}{2} a^{5} - \frac{1}{2} a^{3} - \frac{1}{2} a - \frac{1}{3}$, $\frac{1}{12} a^{13} - \frac{1}{4} a^{11} - \frac{1}{12} a^{7} - \frac{1}{2} a^{6} - \frac{1}{2} a^{4} - \frac{1}{4} a^{3} - \frac{1}{2} a^{2} + \frac{1}{12} a$, $\frac{1}{48} a^{14} - \frac{1}{16} a^{12} + \frac{1}{8} a^{10} - \frac{7}{48} a^{8} - \frac{1}{8} a^{6} - \frac{1}{2} a^{5} - \frac{5}{16} a^{4} - \frac{1}{2} a^{3} - \frac{23}{48} a^{2} - \frac{1}{2} a$, $\frac{1}{384} a^{15} - \frac{1}{96} a^{14} - \frac{1}{128} a^{13} + \frac{1}{32} a^{12} - \frac{3}{64} a^{11} + \frac{3}{16} a^{10} - \frac{79}{384} a^{9} - \frac{17}{96} a^{8} - \frac{9}{64} a^{7} - \frac{7}{16} a^{6} + \frac{3}{128} a^{5} - \frac{3}{32} a^{4} - \frac{47}{384} a^{3} + \frac{47}{96} a^{2} - \frac{3}{8} a - \frac{1}{2}$, $\frac{1}{1426643735040} a^{16} - \frac{1775924567}{285328747008} a^{14} - \frac{28510182529}{713321867520} a^{12} + \frac{14800982033}{1426643735040} a^{10} + \frac{36573066893}{713321867520} a^{8} + \frac{214369645097}{1426643735040} a^{6} - \frac{1}{2} a^{5} + \frac{108536472557}{285328747008} a^{4} - \frac{1}{2} a^{3} + \frac{7444141547}{22291308360} a^{2} - \frac{1}{2} a - \frac{2725691897}{5572827090}$, $\frac{1}{5706574940160} a^{17} + \frac{1196249881}{1141314988032} a^{15} - \frac{1}{96} a^{14} - \frac{50801490889}{2853287470080} a^{13} + \frac{1}{32} a^{12} - \frac{252694718287}{5706574940160} a^{11} + \frac{3}{16} a^{10} + \frac{519551414693}{2853287470080} a^{9} - \frac{17}{96} a^{8} + \frac{125204411657}{5706574940160} a^{7} - \frac{7}{16} a^{6} + \frac{277950416093}{1141314988032} a^{5} - \frac{3}{32} a^{4} + \frac{164453220863}{356660933760} a^{3} + \frac{47}{96} a^{2} - \frac{2756052721}{11145654180} a - \frac{1}{2}$

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

Class group and class number

$C_{3}\times C_{6}$, which has order $18$ (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:  $8$
magma: UnitRank(K);
 
sage: UK.rank()
 
gp: K.fu
 
Torsion generator:  \( -\frac{904899}{1387448320} a^{17} + \frac{316965}{277489664} a^{15} + \frac{10542771}{693724160} a^{13} - \frac{151023027}{1387448320} a^{11} - \frac{764564407}{693724160} a^{9} - \frac{4858652283}{1387448320} a^{7} - \frac{1242259623}{277489664} a^{5} - \frac{4617471}{43357760} a^{3} + \frac{21092943}{5419720} a \) (order $4$)
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:  \( 7680092.907178393 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$C_2\times C_3:S_3$ (as 18T12):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A solvable group of order 36
The 12 conjugacy class representatives for $C_2\times C_3:S_3$
Character table for $C_2\times C_3:S_3$

Intermediate fields

\(\Q(\sqrt{-1}) \), 3.1.3267.1, 3.1.1452.1, 3.1.108.1, 3.1.13068.1, 6.0.33732864.1, 6.0.683090496.4, 6.0.186624.1, 6.0.2732361984.1, 9.1.6694969951296.1

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 18 sibling: 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 ${\href{/LocalNumberField/5.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/5.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/7.6.0.1}{6} }^{3}$ R ${\href{/LocalNumberField/13.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/17.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/17.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/19.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/23.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/29.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/29.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/31.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/37.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/41.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/41.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/43.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/47.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/53.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/53.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/59.2.0.1}{2} }^{9}$

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$2.6.8.1$x^{6} + 2 x^{3} + 2$$6$$1$$8$$D_{6}$$[2]_{3}^{2}$
2.12.16.13$x^{12} + 12 x^{10} + 12 x^{8} + 8 x^{6} + 32 x^{4} - 16 x^{2} + 16$$6$$2$$16$$D_6$$[2]_{3}^{2}$
$3$3.6.6.3$x^{6} + 3 x^{4} + 9$$3$$2$$6$$D_{6}$$[3/2]_{2}^{2}$
3.12.14.6$x^{12} + 3 x^{11} + 3 x^{10} - 6 x^{9} + 3 x^{8} + 9 x^{7} + 9 x^{4} + 9 x^{3} + 9$$6$$2$$14$$D_6$$[3/2]_{2}^{2}$
$11$11.6.4.1$x^{6} + 220 x^{3} + 41503$$3$$2$$4$$S_3$$[\ ]_{3}^{2}$
11.6.4.1$x^{6} + 220 x^{3} + 41503$$3$$2$$4$$S_3$$[\ ]_{3}^{2}$
11.6.4.1$x^{6} + 220 x^{3} + 41503$$3$$2$$4$$S_3$$[\ ]_{3}^{2}$