Properties

Label 18.18.1362017694...0672.1
Degree $18$
Signature $[18, 0]$
Discriminant $2^{18}\cdot 3^{9}\cdot 1129^{8}$
Root discriminant $78.77$
Ramified primes $2, 3, 1129$
Class number $1$ (GRH)
Class group Trivial (GRH)
Galois group $D_{18}$ (as 18T13)

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![109, -564, -3288, 12148, 34798, -59266, -101484, 120652, 86432, -93216, -23739, 30696, 932, -4460, 350, 280, -38, -6, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^18 - 6*x^17 - 38*x^16 + 280*x^15 + 350*x^14 - 4460*x^13 + 932*x^12 + 30696*x^11 - 23739*x^10 - 93216*x^9 + 86432*x^8 + 120652*x^7 - 101484*x^6 - 59266*x^5 + 34798*x^4 + 12148*x^3 - 3288*x^2 - 564*x + 109)
 
gp: K = bnfinit(x^18 - 6*x^17 - 38*x^16 + 280*x^15 + 350*x^14 - 4460*x^13 + 932*x^12 + 30696*x^11 - 23739*x^10 - 93216*x^9 + 86432*x^8 + 120652*x^7 - 101484*x^6 - 59266*x^5 + 34798*x^4 + 12148*x^3 - 3288*x^2 - 564*x + 109, 1)
 

Normalized defining polynomial

\( x^{18} - 6 x^{17} - 38 x^{16} + 280 x^{15} + 350 x^{14} - 4460 x^{13} + 932 x^{12} + 30696 x^{11} - 23739 x^{10} - 93216 x^{9} + 86432 x^{8} + 120652 x^{7} - 101484 x^{6} - 59266 x^{5} + 34798 x^{4} + 12148 x^{3} - 3288 x^{2} - 564 x + 109 \)

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

Invariants

Degree:  $18$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[18, 0]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(13620176948980906425236472453660672=2^{18}\cdot 3^{9}\cdot 1129^{8}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $78.77$
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:  $2, 3, 1129$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $a^{15}$, $\frac{1}{4199} a^{16} - \frac{639}{4199} a^{15} - \frac{30}{323} a^{14} - \frac{462}{4199} a^{13} - \frac{523}{4199} a^{12} - \frac{1362}{4199} a^{11} - \frac{115}{323} a^{10} + \frac{1896}{4199} a^{9} + \frac{1044}{4199} a^{8} + \frac{9}{4199} a^{7} - \frac{617}{4199} a^{6} + \frac{116}{4199} a^{5} + \frac{92}{323} a^{4} - \frac{1436}{4199} a^{3} - \frac{1743}{4199} a^{2} - \frac{14}{4199} a - \frac{1999}{4199}$, $\frac{1}{495592318845721493905131846119} a^{17} + \frac{52622567534171960477313678}{495592318845721493905131846119} a^{16} - \frac{86845420254241814164496318677}{495592318845721493905131846119} a^{15} - \frac{5311756428627284634882457923}{17089390305024879100176960211} a^{14} + \frac{177529547592763400170761799217}{495592318845721493905131846119} a^{13} + \frac{8098657668409352965639563021}{29152489343865970229713638007} a^{12} + \frac{11472131985860705740674980584}{29152489343865970229713638007} a^{11} - \frac{178821181857095500771481582866}{495592318845721493905131846119} a^{10} + \frac{107024398583711988959469830284}{495592318845721493905131846119} a^{9} - \frac{53703031825800881969451675014}{495592318845721493905131846119} a^{8} - \frac{169091363465271992028364386113}{495592318845721493905131846119} a^{7} + \frac{45681986622596379034022456795}{495592318845721493905131846119} a^{6} + \frac{233215486358487906847071043417}{495592318845721493905131846119} a^{5} + \frac{76387488063041928686492961090}{495592318845721493905131846119} a^{4} + \frac{192201465852386345675738666695}{495592318845721493905131846119} a^{3} - \frac{6999416075642892324762477954}{38122486065055499531163988163} a^{2} - \frac{9747462986942533398347937563}{29152489343865970229713638007} a + \frac{165597214091235437877460185439}{495592318845721493905131846119}$

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:  $17$
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:  \( 236007763005 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$D_{18}$ (as 18T13):

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 $D_{18}$
Character table for $D_{18}$

Intermediate fields

\(\Q(\sqrt{3}) \), 3.3.1129.1, 6.6.2202579648.2, 9.9.1624709678881.1

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 $18$ $18$ ${\href{/LocalNumberField/11.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/11.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/13.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/13.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/17.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/19.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/23.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/29.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/31.2.0.1}{2} }^{9}$ ${\href{/LocalNumberField/37.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/37.1.0.1}{1} }^{2}$ ${\href{/LocalNumberField/41.2.0.1}{2} }^{9}$ $18$ ${\href{/LocalNumberField/47.9.0.1}{9} }^{2}$ $18$ ${\href{/LocalNumberField/59.2.0.1}{2} }^{8}{,}\,{\href{/LocalNumberField/59.1.0.1}{1} }^{2}$

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
2Data not computed
$3$3.6.3.1$x^{6} - 6 x^{4} + 9 x^{2} - 27$$2$$3$$3$$C_6$$[\ ]_{2}^{3}$
3.6.3.1$x^{6} - 6 x^{4} + 9 x^{2} - 27$$2$$3$$3$$C_6$$[\ ]_{2}^{3}$
3.6.3.1$x^{6} - 6 x^{4} + 9 x^{2} - 27$$2$$3$$3$$C_6$$[\ ]_{2}^{3}$
1129Data not computed