Properties

Label 18.2.27772539334...5888.1
Degree $18$
Signature $[2, 8]$
Discriminant $2^{24}\cdot 3^{20}\cdot 7^{15}$
Root discriminant $43.23$
Ramified primes $2, 3, 7$
Class number $9$ (GRH)
Class group $[3, 3]$ (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![-27, 0, 0, -634, 0, 0, 205, 0, 0, -1114, 0, 0, 235, 0, 0, -16, 0, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^18 - 16*x^15 + 235*x^12 - 1114*x^9 + 205*x^6 - 634*x^3 - 27)
 
gp: K = bnfinit(x^18 - 16*x^15 + 235*x^12 - 1114*x^9 + 205*x^6 - 634*x^3 - 27, 1)
 

Normalized defining polynomial

\( x^{18} - 16 x^{15} + 235 x^{12} - 1114 x^{9} + 205 x^{6} - 634 x^{3} - 27 \)

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:  \(277725393348739612841122725888=2^{24}\cdot 3^{20}\cdot 7^{15}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $43.23$
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:  $2, 3, 7$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $\frac{1}{3} a^{7} - \frac{1}{3} a$, $\frac{1}{9} a^{8} - \frac{4}{9} a^{2}$, $\frac{1}{9} a^{9} - \frac{4}{9} a^{3}$, $\frac{1}{9} a^{10} - \frac{4}{9} a^{4}$, $\frac{1}{9} a^{11} - \frac{4}{9} a^{5}$, $\frac{1}{45} a^{12} + \frac{2}{45} a^{9} + \frac{14}{45} a^{6} + \frac{19}{45} a^{3} + \frac{1}{5}$, $\frac{1}{45} a^{13} + \frac{2}{45} a^{10} - \frac{1}{45} a^{7} + \frac{19}{45} a^{4} - \frac{7}{15} a$, $\frac{1}{135} a^{14} - \frac{1}{135} a^{13} + \frac{1}{135} a^{12} + \frac{2}{135} a^{11} - \frac{2}{135} a^{10} + \frac{2}{135} a^{9} - \frac{1}{135} a^{8} - \frac{14}{135} a^{7} - \frac{31}{135} a^{6} + \frac{19}{135} a^{5} - \frac{19}{135} a^{4} + \frac{19}{135} a^{3} - \frac{22}{45} a^{2} - \frac{1}{15} a + \frac{2}{5}$, $\frac{1}{1741905} a^{15} - \frac{1064}{193545} a^{12} + \frac{77428}{1741905} a^{9} + \frac{6458}{193545} a^{6} - \frac{249383}{1741905} a^{3} - \frac{2366}{64515}$, $\frac{1}{1741905} a^{16} - \frac{1064}{193545} a^{13} + \frac{77428}{1741905} a^{10} + \frac{6458}{193545} a^{7} - \frac{249383}{1741905} a^{4} - \frac{2366}{64515} a$, $\frac{1}{5225715} a^{17} + \frac{1}{5225715} a^{16} + \frac{1}{5225715} a^{15} - \frac{1064}{580635} a^{14} - \frac{1064}{580635} a^{13} - \frac{1064}{580635} a^{12} + \frac{270973}{5225715} a^{11} + \frac{270973}{5225715} a^{10} + \frac{270973}{5225715} a^{9} + \frac{6458}{580635} a^{8} + \frac{6458}{580635} a^{7} + \frac{200003}{580635} a^{6} + \frac{2460247}{5225715} a^{5} + \frac{2460247}{5225715} a^{4} + \frac{2460247}{5225715} a^{3} - \frac{66881}{193545} a^{2} - \frac{66881}{193545} a + \frac{62149}{193545}$

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

Class group and class number

$C_{3}\times C_{3}$, 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:  \( 36893677.6319196 \) (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

\(\Q(\sqrt{7}) \), 3.1.108.1, 3.1.5292.1, 3.1.1323.1, 3.1.588.1, 6.2.64012032.1, 6.2.784147392.1, 6.2.3136589568.1, 6.2.38723328.1, 9.1.444611571264.1

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 ${\href{/LocalNumberField/5.2.0.1}{2} }^{9}$ R ${\href{/LocalNumberField/11.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/13.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/17.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/19.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/23.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/29.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/29.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/31.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/37.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/41.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/43.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/47.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/47.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/53.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/53.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/59.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/59.1.0.1}{1} }^{2}$

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$2.6.8.1$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$3.3.3.2$x^{3} + 3 x + 3$$3$$1$$3$$S_3$$[3/2]_{2}$
3.3.3.2$x^{3} + 3 x + 3$$3$$1$$3$$S_3$$[3/2]_{2}$
3.6.7.4$x^{6} + 3 x^{2} + 3$$6$$1$$7$$S_3$$[3/2]_{2}$
3.6.7.4$x^{6} + 3 x^{2} + 3$$6$$1$$7$$S_3$$[3/2]_{2}$
7Data not computed