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Properties

Label 18.10.1463561466...0873.1
Degree $18$
Signature $[10, 4]$
Discriminant $7^{12}\cdot 41^{5}\cdot 97^{3}$
Root discriminant $22.01$
Ramified primes $7, 41, 97$
Class number $1$ (GRH)
Class group Trivial (GRH)
Galois group 18T401

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![-1, 8, 46, -253, 363, 161, -1192, 932, 1333, -2231, 61, 1369, -407, -357, 145, 43, -20, -2, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^18 - 2*x^17 - 20*x^16 + 43*x^15 + 145*x^14 - 357*x^13 - 407*x^12 + 1369*x^11 + 61*x^10 - 2231*x^9 + 1333*x^8 + 932*x^7 - 1192*x^6 + 161*x^5 + 363*x^4 - 253*x^3 + 46*x^2 + 8*x - 1)
 
gp: K = bnfinit(x^18 - 2*x^17 - 20*x^16 + 43*x^15 + 145*x^14 - 357*x^13 - 407*x^12 + 1369*x^11 + 61*x^10 - 2231*x^9 + 1333*x^8 + 932*x^7 - 1192*x^6 + 161*x^5 + 363*x^4 - 253*x^3 + 46*x^2 + 8*x - 1, 1)
 

Normalized defining polynomial

\( x^{18} - 2 x^{17} - 20 x^{16} + 43 x^{15} + 145 x^{14} - 357 x^{13} - 407 x^{12} + 1369 x^{11} + 61 x^{10} - 2231 x^{9} + 1333 x^{8} + 932 x^{7} - 1192 x^{6} + 161 x^{5} + 363 x^{4} - 253 x^{3} + 46 x^{2} + 8 x - 1 \)

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

Invariants

Degree:  $18$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[10, 4]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(1463561466371433349940873=7^{12}\cdot 41^{5}\cdot 97^{3}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $22.01$
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:  $7, 41, 97$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $a^{15}$, $\frac{1}{41} a^{16} + \frac{17}{41} a^{15} + \frac{18}{41} a^{14} + \frac{9}{41} a^{13} - \frac{17}{41} a^{12} - \frac{6}{41} a^{11} + \frac{19}{41} a^{10} - \frac{4}{41} a^{9} - \frac{18}{41} a^{8} + \frac{2}{41} a^{7} - \frac{18}{41} a^{6} + \frac{20}{41} a^{5} + \frac{13}{41} a^{4} - \frac{3}{41} a^{3} + \frac{4}{41} a^{2} - \frac{19}{41} a - \frac{20}{41}$, $\frac{1}{1774066683090283} a^{17} - \frac{16975241569929}{1774066683090283} a^{16} + \frac{327952358329138}{1774066683090283} a^{15} + \frac{841937909091234}{1774066683090283} a^{14} - \frac{692035983058856}{1774066683090283} a^{13} - \frac{829220367407723}{1774066683090283} a^{12} - \frac{430073265890865}{1774066683090283} a^{11} + \frac{253545468590095}{1774066683090283} a^{10} - \frac{654047089037186}{1774066683090283} a^{9} - \frac{670321327765834}{1774066683090283} a^{8} + \frac{22138701177480}{1774066683090283} a^{7} + \frac{53683696152052}{1774066683090283} a^{6} - \frac{869395369886658}{1774066683090283} a^{5} + \frac{557985687913540}{1774066683090283} a^{4} - \frac{692970756468791}{1774066683090283} a^{3} - \frac{435897787113868}{1774066683090283} a^{2} + \frac{179547325033879}{1774066683090283} a + \frac{685459388425519}{1774066683090283}$

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:  $13$
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:  \( 238603.851728 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

18T401:

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A solvable group of order 2592
The 44 conjugacy class representatives for t18n401
Character table for t18n401 is not computed

Intermediate fields

\(\Q(\zeta_{7})^+\), 6.6.9548777.1, 9.5.467890073.1

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 ${\href{/LocalNumberField/2.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/3.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/5.6.0.1}{6} }^{3}$ R ${\href{/LocalNumberField/11.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/13.6.0.1}{6} }^{2}{,}\,{\href{/LocalNumberField/13.3.0.1}{3} }^{2}$ ${\href{/LocalNumberField/17.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/19.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/23.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/29.3.0.1}{3} }^{2}{,}\,{\href{/LocalNumberField/29.2.0.1}{2} }^{6}$ ${\href{/LocalNumberField/31.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/37.6.0.1}{6} }^{3}$ R ${\href{/LocalNumberField/43.6.0.1}{6} }{,}\,{\href{/LocalNumberField/43.2.0.1}{2} }^{5}{,}\,{\href{/LocalNumberField/43.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/47.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/53.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/59.6.0.1}{6} }^{3}$

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
$7$7.9.6.1$x^{9} + 42 x^{6} + 539 x^{3} + 2744$$3$$3$$6$$C_3^2$$[\ ]_{3}^{3}$
7.9.6.1$x^{9} + 42 x^{6} + 539 x^{3} + 2744$$3$$3$$6$$C_3^2$$[\ ]_{3}^{3}$
41Data not computed
97Data not computed