Properties

Label 18.0.11088656920...9375.2
Degree $18$
Signature $[0, 9]$
Discriminant $-\,3^{9}\cdot 5^{9}\cdot 19^{16}$
Root discriminant $53.05$
Ramified primes $3, 5, 19$
Class number $3258$ (GRH)
Class group $[3258]$ (GRH)
Galois group $C_{18}$ (as 18T1)

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![4775041, -2913750, 5123532, -2907231, 2800752, -1439914, 999805, -459765, 254065, -103535, 47380, -16865, 6508, -1979, 627, -154, 40, -7, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^18 - 7*x^17 + 40*x^16 - 154*x^15 + 627*x^14 - 1979*x^13 + 6508*x^12 - 16865*x^11 + 47380*x^10 - 103535*x^9 + 254065*x^8 - 459765*x^7 + 999805*x^6 - 1439914*x^5 + 2800752*x^4 - 2907231*x^3 + 5123532*x^2 - 2913750*x + 4775041)
 
gp: K = bnfinit(x^18 - 7*x^17 + 40*x^16 - 154*x^15 + 627*x^14 - 1979*x^13 + 6508*x^12 - 16865*x^11 + 47380*x^10 - 103535*x^9 + 254065*x^8 - 459765*x^7 + 999805*x^6 - 1439914*x^5 + 2800752*x^4 - 2907231*x^3 + 5123532*x^2 - 2913750*x + 4775041, 1)
 

Normalized defining polynomial

\( x^{18} - 7 x^{17} + 40 x^{16} - 154 x^{15} + 627 x^{14} - 1979 x^{13} + 6508 x^{12} - 16865 x^{11} + 47380 x^{10} - 103535 x^{9} + 254065 x^{8} - 459765 x^{7} + 999805 x^{6} - 1439914 x^{5} + 2800752 x^{4} - 2907231 x^{3} + 5123532 x^{2} - 2913750 x + 4775041 \)

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:  \(-11088656920413061413017818359375=-\,3^{9}\cdot 5^{9}\cdot 19^{16}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $53.05$
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:  $3, 5, 19$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is Galois and abelian over $\Q$.
Conductor:  \(285=3\cdot 5\cdot 19\)
Dirichlet character group:    $\lbrace$$\chi_{285}(256,·)$, $\chi_{285}(1,·)$, $\chi_{285}(194,·)$, $\chi_{285}(196,·)$, $\chi_{285}(134,·)$, $\chi_{285}(74,·)$, $\chi_{285}(271,·)$, $\chi_{285}(16,·)$, $\chi_{285}(149,·)$, $\chi_{285}(226,·)$, $\chi_{285}(104,·)$, $\chi_{285}(106,·)$, $\chi_{285}(44,·)$, $\chi_{285}(239,·)$, $\chi_{285}(119,·)$, $\chi_{285}(121,·)$, $\chi_{285}(61,·)$, $\chi_{285}(254,·)$$\rbrace$
This is a CM field.

Integral basis (with respect to field generator \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $a^{15}$, $a^{16}$, $\frac{1}{7411501356656592181466203321313077133973321331} a^{17} + \frac{1682738557907462545045773902922109084413913964}{7411501356656592181466203321313077133973321331} a^{16} + \frac{807522237229070266785860172624574478394746143}{7411501356656592181466203321313077133973321331} a^{15} + \frac{3398915715717610630137767161978683054574047668}{7411501356656592181466203321313077133973321331} a^{14} + \frac{2803081509103715947408754993061402201436382873}{7411501356656592181466203321313077133973321331} a^{13} - \frac{2298919975841044920010086129573228354087374348}{7411501356656592181466203321313077133973321331} a^{12} + \frac{424812794607696096264682100288037127173099089}{7411501356656592181466203321313077133973321331} a^{11} - \frac{2550839963118580214330867815738611093421574762}{7411501356656592181466203321313077133973321331} a^{10} - \frac{2285797400678778670964227612058408818528450861}{7411501356656592181466203321313077133973321331} a^{9} + \frac{2623412566824055181176797016160328164037023527}{7411501356656592181466203321313077133973321331} a^{8} + \frac{367009032232930439810849131902243081927375967}{7411501356656592181466203321313077133973321331} a^{7} + \frac{139159286028700338682990362052094353250244097}{7411501356656592181466203321313077133973321331} a^{6} + \frac{2816671644350102722163992888380535265358707326}{7411501356656592181466203321313077133973321331} a^{5} + \frac{149896263902877470385714319453385511949720650}{7411501356656592181466203321313077133973321331} a^{4} + \frac{2633693025092469994085482100065244444696004381}{7411501356656592181466203321313077133973321331} a^{3} - \frac{211392910844076151177367916561474670881743050}{7411501356656592181466203321313077133973321331} a^{2} + \frac{3310924754130500478352795312724776283878867870}{7411501356656592181466203321313077133973321331} a - \frac{121516822687688678596241730506059675462611316}{7411501356656592181466203321313077133973321331}$

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

Class group and class number

$C_{3258}$, which has order $3258$ (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:  \( -1 \) (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:  \( 22305.8950792 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$C_{18}$ (as 18T1):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A cyclic group of order 18
The 18 conjugacy class representatives for $C_{18}$
Character table for $C_{18}$

Intermediate fields

\(\Q(\sqrt{-15}) \), 3.3.361.1, 6.0.439833375.1, \(\Q(\zeta_{19})^+\)

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

Frobenius cycle types

$p$ 2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59
Cycle type ${\href{/LocalNumberField/2.9.0.1}{9} }^{2}$ R R ${\href{/LocalNumberField/7.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/11.6.0.1}{6} }^{3}$ $18$ ${\href{/LocalNumberField/17.9.0.1}{9} }^{2}$ R ${\href{/LocalNumberField/23.9.0.1}{9} }^{2}$ $18$ ${\href{/LocalNumberField/31.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/37.2.0.1}{2} }^{9}$ $18$ $18$ ${\href{/LocalNumberField/47.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/53.9.0.1}{9} }^{2}$ $18$

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
3Data not computed
5Data not computed
$19$19.9.8.8$x^{9} - 19$$9$$1$$8$$C_9$$[\ ]_{9}$
19.9.8.8$x^{9} - 19$$9$$1$$8$$C_9$$[\ ]_{9}$