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Properties

Label 18.8.15191184967...9351.2
Degree $18$
Signature $[8, 5]$
Discriminant $-\,7^{12}\cdot 97^{2}\cdot 22679^{3}$
Root discriminant $32.37$
Ramified primes $7, 97, 22679$
Class number $2$ (GRH)
Class group $[2]$ (GRH)
Galois group 18T840

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![-5333, 11217, 10383, -15768, -22674, -11138, 7835, 10160, 3265, -424, -1266, -220, -107, -2, 32, 8, 9, -7, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^18 - 7*x^17 + 9*x^16 + 8*x^15 + 32*x^14 - 2*x^13 - 107*x^12 - 220*x^11 - 1266*x^10 - 424*x^9 + 3265*x^8 + 10160*x^7 + 7835*x^6 - 11138*x^5 - 22674*x^4 - 15768*x^3 + 10383*x^2 + 11217*x - 5333)
 
gp: K = bnfinit(x^18 - 7*x^17 + 9*x^16 + 8*x^15 + 32*x^14 - 2*x^13 - 107*x^12 - 220*x^11 - 1266*x^10 - 424*x^9 + 3265*x^8 + 10160*x^7 + 7835*x^6 - 11138*x^5 - 22674*x^4 - 15768*x^3 + 10383*x^2 + 11217*x - 5333, 1)
 

Normalized defining polynomial

\( x^{18} - 7 x^{17} + 9 x^{16} + 8 x^{15} + 32 x^{14} - 2 x^{13} - 107 x^{12} - 220 x^{11} - 1266 x^{10} - 424 x^{9} + 3265 x^{8} + 10160 x^{7} + 7835 x^{6} - 11138 x^{5} - 22674 x^{4} - 15768 x^{3} + 10383 x^{2} + 11217 x - 5333 \)

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

Invariants

Degree:  $18$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[8, 5]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(-1519118496790264747045229351=-\,7^{12}\cdot 97^{2}\cdot 22679^{3}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $32.37$
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:  $7, 97, 22679$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $a^{15}$, $a^{16}$, $\frac{1}{1180817215619915090769112310259150257} a^{17} - \frac{96356056347411070256019556880973062}{1180817215619915090769112310259150257} a^{16} + \frac{169435845825950853968732532047676554}{1180817215619915090769112310259150257} a^{15} - \frac{41936739646029587021658476536772340}{1180817215619915090769112310259150257} a^{14} - \frac{313192643595142302653070276843884932}{1180817215619915090769112310259150257} a^{13} - \frac{539649221782270837747152339801065928}{1180817215619915090769112310259150257} a^{12} + \frac{146795954690349642277229540986420374}{1180817215619915090769112310259150257} a^{11} - \frac{110761523004337238304196787043347013}{1180817215619915090769112310259150257} a^{10} + \frac{180875315335186880421506610577796493}{1180817215619915090769112310259150257} a^{9} + \frac{292327484497806295485715244153714983}{1180817215619915090769112310259150257} a^{8} - \frac{460264243332547549620848494854843075}{1180817215619915090769112310259150257} a^{7} - \frac{461077986124437756459315430603244455}{1180817215619915090769112310259150257} a^{6} - \frac{535847853544055826022706865469090863}{1180817215619915090769112310259150257} a^{5} - \frac{275657188583208105625634754967133520}{1180817215619915090769112310259150257} a^{4} + \frac{26399701058082397530712067504665385}{1180817215619915090769112310259150257} a^{3} + \frac{283521588203605358265909820949272156}{1180817215619915090769112310259150257} a^{2} + \frac{390061520562281070513421489473079034}{1180817215619915090769112310259150257} a + \frac{48736183893381934878444104867044271}{1180817215619915090769112310259150257}$

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

Class group and class number

$C_{2}$, which has order $2$ (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:  $12$
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:  \( 2859361.34505 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

18T840:

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A solvable group of order 165888
The 180 conjugacy class representatives for t18n840 are not computed
Character table for t18n840 is not computed

Intermediate fields

\(\Q(\zeta_{7})^+\), 9.7.2668161671.1

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 ${\href{/LocalNumberField/2.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/3.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/5.9.0.1}{9} }^{2}$ R ${\href{/LocalNumberField/11.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/13.6.0.1}{6} }^{2}{,}\,{\href{/LocalNumberField/13.4.0.1}{4} }{,}\,{\href{/LocalNumberField/13.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/17.6.0.1}{6} }^{2}{,}\,{\href{/LocalNumberField/17.3.0.1}{3} }^{2}$ ${\href{/LocalNumberField/19.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/23.12.0.1}{12} }{,}\,{\href{/LocalNumberField/23.3.0.1}{3} }^{2}$ ${\href{/LocalNumberField/29.4.0.1}{4} }{,}\,{\href{/LocalNumberField/29.3.0.1}{3} }^{2}{,}\,{\href{/LocalNumberField/29.2.0.1}{2} }^{3}{,}\,{\href{/LocalNumberField/29.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/31.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/37.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/41.4.0.1}{4} }{,}\,{\href{/LocalNumberField/41.3.0.1}{3} }^{4}{,}\,{\href{/LocalNumberField/41.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/43.6.0.1}{6} }{,}\,{\href{/LocalNumberField/43.4.0.1}{4} }^{2}{,}\,{\href{/LocalNumberField/43.2.0.1}{2} }{,}\,{\href{/LocalNumberField/43.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/47.12.0.1}{12} }{,}\,{\href{/LocalNumberField/47.3.0.1}{3} }^{2}$ ${\href{/LocalNumberField/53.12.0.1}{12} }{,}\,{\href{/LocalNumberField/53.3.0.1}{3} }^{2}$ ${\href{/LocalNumberField/59.9.0.1}{9} }^{2}$

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
$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}$
97Data not computed
22679Data not computed