Properties

Label 18.0.32280357562...3327.1
Degree $18$
Signature $[0, 9]$
Discriminant $-\,19^{16}\cdot 47^{9}$
Root discriminant $93.91$
Ramified primes $19, 47$
Class number $638885$ (GRH)
Class group $[638885]$ (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![16620397249, -6299768998, 9558403988, -3182071487, 2545728128, -741082426, 410585125, -103781941, 44088281, -9555455, 3262588, -592865, 166052, -24267, 5587, -602, 112, -7, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^18 - 7*x^17 + 112*x^16 - 602*x^15 + 5587*x^14 - 24267*x^13 + 166052*x^12 - 592865*x^11 + 3262588*x^10 - 9555455*x^9 + 44088281*x^8 - 103781941*x^7 + 410585125*x^6 - 741082426*x^5 + 2545728128*x^4 - 3182071487*x^3 + 9558403988*x^2 - 6299768998*x + 16620397249)
 
gp: K = bnfinit(x^18 - 7*x^17 + 112*x^16 - 602*x^15 + 5587*x^14 - 24267*x^13 + 166052*x^12 - 592865*x^11 + 3262588*x^10 - 9555455*x^9 + 44088281*x^8 - 103781941*x^7 + 410585125*x^6 - 741082426*x^5 + 2545728128*x^4 - 3182071487*x^3 + 9558403988*x^2 - 6299768998*x + 16620397249, 1)
 

Normalized defining polynomial

\( x^{18} - 7 x^{17} + 112 x^{16} - 602 x^{15} + 5587 x^{14} - 24267 x^{13} + 166052 x^{12} - 592865 x^{11} + 3262588 x^{10} - 9555455 x^{9} + 44088281 x^{8} - 103781941 x^{7} + 410585125 x^{6} - 741082426 x^{5} + 2545728128 x^{4} - 3182071487 x^{3} + 9558403988 x^{2} - 6299768998 x + 16620397249 \)

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:  \(-322803575628362753619753567652073327=-\,19^{16}\cdot 47^{9}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $93.91$
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:  $19, 47$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is Galois and abelian over $\Q$.
Conductor:  \(893=19\cdot 47\)
Dirichlet character group:    $\lbrace$$\chi_{893}(704,·)$, $\chi_{893}(1,·)$, $\chi_{893}(518,·)$, $\chi_{893}(328,·)$, $\chi_{893}(330,·)$, $\chi_{893}(140,·)$, $\chi_{893}(845,·)$, $\chi_{893}(142,·)$, $\chi_{893}(847,·)$, $\chi_{893}(657,·)$, $\chi_{893}(283,·)$, $\chi_{893}(93,·)$, $\chi_{893}(612,·)$, $\chi_{893}(422,·)$, $\chi_{893}(424,·)$, $\chi_{893}(234,·)$, $\chi_{893}(377,·)$, $\chi_{893}(187,·)$$\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}{30842318782880889138534410535178268647280406237534945274681811} a^{17} - \frac{469750728531593939920515600839328318930248141270424177690833}{30842318782880889138534410535178268647280406237534945274681811} a^{16} + \frac{6457285124165235285174031746295470027323375841206324635807613}{30842318782880889138534410535178268647280406237534945274681811} a^{15} + \frac{11381217484306730209370460861547182156299915912127476524968097}{30842318782880889138534410535178268647280406237534945274681811} a^{14} - \frac{11573967423652202299112676806138818211523678272466883201279239}{30842318782880889138534410535178268647280406237534945274681811} a^{13} - \frac{11115207560916024212302199113996684310299562668279426328973952}{30842318782880889138534410535178268647280406237534945274681811} a^{12} + \frac{12583503049649324852524319484759346533801049791813288363353479}{30842318782880889138534410535178268647280406237534945274681811} a^{11} + \frac{332839145298256279797986575379621488021225974019812306002056}{833576183321105111852281365815628882358929898311755277694103} a^{10} - \frac{6393490498796527543922784105764280043663576541632772798416438}{30842318782880889138534410535178268647280406237534945274681811} a^{9} - \frac{10957658441084305966973247333655086093653399732232732096564252}{30842318782880889138534410535178268647280406237534945274681811} a^{8} - \frac{4390605159900554610162989312252137812938474010809679121544660}{30842318782880889138534410535178268647280406237534945274681811} a^{7} - \frac{4962971937074626170338292323116149763458865605945778998560529}{30842318782880889138534410535178268647280406237534945274681811} a^{6} + \frac{5162944625102315474771005425867494558228223878702515965446972}{30842318782880889138534410535178268647280406237534945274681811} a^{5} + \frac{6396597964200463551146523706873813771290661782267455277504142}{30842318782880889138534410535178268647280406237534945274681811} a^{4} - \frac{7939082058396512298225252011809833815075136077858145159664135}{30842318782880889138534410535178268647280406237534945274681811} a^{3} + \frac{12771648913256077996116901089625320246363023816111851216075160}{30842318782880889138534410535178268647280406237534945274681811} a^{2} + \frac{13806405400263415973584454711840114301413723849902823306826247}{30842318782880889138534410535178268647280406237534945274681811} a - \frac{13249725876982095381098200343711073853188098462242353303846828}{30842318782880889138534410535178268647280406237534945274681811}$

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

Class group and class number

$C_{638885}$, which has order $638885$ (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

\(\Q(\sqrt{-47}) \), 3.3.361.1, 6.0.13530317183.1, \(\Q(\zeta_{19})^+\)

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 ${\href{/LocalNumberField/2.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/3.9.0.1}{9} }^{2}$ $18$ ${\href{/LocalNumberField/7.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/11.6.0.1}{6} }^{3}$ $18$ ${\href{/LocalNumberField/17.9.0.1}{9} }^{2}$ R $18$ $18$ ${\href{/LocalNumberField/31.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/37.1.0.1}{1} }^{18}$ $18$ $18$ R ${\href{/LocalNumberField/53.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/59.9.0.1}{9} }^{2}$

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
19Data not computed
47Data not computed