Properties

Label 18.0.42141281534...2091.1
Degree $18$
Signature $[0, 9]$
Discriminant $-\,3^{44}\cdot 7^{9}\cdot 13^{9}$
Root discriminant $139.90$
Ramified primes $3, 7, 13$
Class number $12212858$ (GRH)
Class group $[7, 7, 249242]$ (GRH)
Galois group $C_{18}$ (as 18T1)

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magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![3709960454951, -1144383031881, 1307472810363, -340247545008, 206139713310, -45526465413, 19116861729, -3577518954, 1149875379, -180492362, 46502352, -5986422, 1262352, -127512, 22104, -1596, 225, -9, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^18 - 9*x^17 + 225*x^16 - 1596*x^15 + 22104*x^14 - 127512*x^13 + 1262352*x^12 - 5986422*x^11 + 46502352*x^10 - 180492362*x^9 + 1149875379*x^8 - 3577518954*x^7 + 19116861729*x^6 - 45526465413*x^5 + 206139713310*x^4 - 340247545008*x^3 + 1307472810363*x^2 - 1144383031881*x + 3709960454951)
 
gp: K = bnfinit(x^18 - 9*x^17 + 225*x^16 - 1596*x^15 + 22104*x^14 - 127512*x^13 + 1262352*x^12 - 5986422*x^11 + 46502352*x^10 - 180492362*x^9 + 1149875379*x^8 - 3577518954*x^7 + 19116861729*x^6 - 45526465413*x^5 + 206139713310*x^4 - 340247545008*x^3 + 1307472810363*x^2 - 1144383031881*x + 3709960454951, 1)
 

Normalized defining polynomial

\( x^{18} - 9 x^{17} + 225 x^{16} - 1596 x^{15} + 22104 x^{14} - 127512 x^{13} + 1262352 x^{12} - 5986422 x^{11} + 46502352 x^{10} - 180492362 x^{9} + 1149875379 x^{8} - 3577518954 x^{7} + 19116861729 x^{6} - 45526465413 x^{5} + 206139713310 x^{4} - 340247545008 x^{3} + 1307472810363 x^{2} - 1144383031881 x + 3709960454951 \)

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:  \(-421412815345064168757967085957375942091=-\,3^{44}\cdot 7^{9}\cdot 13^{9}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $139.90$
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:  $3, 7, 13$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is Galois and abelian over $\Q$.
Conductor:  \(2457=3^{3}\cdot 7\cdot 13\)
Dirichlet character group:    $\lbrace$$\chi_{2457}(1,·)$, $\chi_{2457}(1093,·)$, $\chi_{2457}(454,·)$, $\chi_{2457}(2185,·)$, $\chi_{2457}(1546,·)$, $\chi_{2457}(274,·)$, $\chi_{2457}(1366,·)$, $\chi_{2457}(727,·)$, $\chi_{2457}(1819,·)$, $\chi_{2457}(547,·)$, $\chi_{2457}(1639,·)$, $\chi_{2457}(1000,·)$, $\chi_{2457}(2092,·)$, $\chi_{2457}(820,·)$, $\chi_{2457}(181,·)$, $\chi_{2457}(1912,·)$, $\chi_{2457}(1273,·)$, $\chi_{2457}(2365,·)$$\rbrace$
This is a CM field.

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

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $\frac{1}{53} a^{15} + \frac{9}{53} a^{14} + \frac{17}{53} a^{13} - \frac{9}{53} a^{12} + \frac{17}{53} a^{11} - \frac{15}{53} a^{10} + \frac{10}{53} a^{9} - \frac{13}{53} a^{8} - \frac{19}{53} a^{7} + \frac{2}{53} a^{6} + \frac{10}{53} a^{5} - \frac{10}{53} a^{4} + \frac{6}{53} a^{3} + \frac{21}{53} a^{2} + \frac{14}{53} a$, $\frac{1}{53} a^{16} - \frac{11}{53} a^{14} - \frac{3}{53} a^{13} - \frac{8}{53} a^{12} - \frac{9}{53} a^{11} - \frac{14}{53} a^{10} + \frac{3}{53} a^{9} - \frac{8}{53} a^{8} + \frac{14}{53} a^{7} - \frac{8}{53} a^{6} + \frac{6}{53} a^{5} - \frac{10}{53} a^{4} + \frac{20}{53} a^{3} - \frac{16}{53} a^{2} - \frac{20}{53} a$, $\frac{1}{65264291491968108645277757355164329728455618909785841099330648975401} a^{17} - \frac{419623535538861732246548222195272242255840949839187274451300667033}{65264291491968108645277757355164329728455618909785841099330648975401} a^{16} + \frac{4028505179086813568585976826110530489641060289249417143028526444}{1231401726263549219722221836889893013744445639807280020742087716517} a^{15} - \frac{14403963765290780067932573645889612807963187386916771508901942908602}{65264291491968108645277757355164329728455618909785841099330648975401} a^{14} - \frac{32400893708323788526896623025505258406537000291069933565516784915908}{65264291491968108645277757355164329728455618909785841099330648975401} a^{13} + \frac{25946471759088718018209378644508471380513917886228903393245920868685}{65264291491968108645277757355164329728455618909785841099330648975401} a^{12} - \frac{7487675093699335393721760445806361856853206782843939696688384498696}{65264291491968108645277757355164329728455618909785841099330648975401} a^{11} + \frac{15919959403252661114707370498986221696024860688379537045274586536778}{65264291491968108645277757355164329728455618909785841099330648975401} a^{10} - \frac{30880940654011952540185933734458100345481605209412510041524166179624}{65264291491968108645277757355164329728455618909785841099330648975401} a^{9} - \frac{15959606035802918184267015840591375415556461013846750754486473944858}{65264291491968108645277757355164329728455618909785841099330648975401} a^{8} + \frac{24877119942680745572684564167134432764374870840865049766414468775268}{65264291491968108645277757355164329728455618909785841099330648975401} a^{7} + \frac{25209536989681017857907480049931965809477272475690843494438452534627}{65264291491968108645277757355164329728455618909785841099330648975401} a^{6} - \frac{16384973766814543759928967651851836537934863723103860266744105905491}{65264291491968108645277757355164329728455618909785841099330648975401} a^{5} - \frac{9571400697604378849192949439950903387412777333586436745178664901821}{65264291491968108645277757355164329728455618909785841099330648975401} a^{4} + \frac{4662525862330453223802354224652240260714101625363114319878039913022}{65264291491968108645277757355164329728455618909785841099330648975401} a^{3} - \frac{8396117893757619265454653017574410220694435072441824461756629127058}{65264291491968108645277757355164329728455618909785841099330648975401} a^{2} + \frac{10039164469000046746707903037953608037677911469295893717141339514707}{65264291491968108645277757355164329728455618909785841099330648975401} a - \frac{369724107224103914635052735884425925933666528430653147255824780059}{1231401726263549219722221836889893013744445639807280020742087716517}$

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

Class group and class number

$C_{7}\times C_{7}\times C_{249242}$, which has order $12212858$ (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:  \( 40934.03294431194 \) (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

\(\Q(\sqrt{-91}) \), \(\Q(\zeta_{9})^+\), 6.0.4944179331.10, \(\Q(\zeta_{27})^+\)

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 $18$ R ${\href{/LocalNumberField/5.9.0.1}{9} }^{2}$ R $18$ R ${\href{/LocalNumberField/17.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/19.3.0.1}{3} }^{6}$ ${\href{/LocalNumberField/23.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/29.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/31.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/37.6.0.1}{6} }^{3}$ ${\href{/LocalNumberField/41.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/43.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/47.9.0.1}{9} }^{2}$ ${\href{/LocalNumberField/53.1.0.1}{1} }^{18}$ ${\href{/LocalNumberField/59.9.0.1}{9} }^{2}$

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
3Data not computed
7Data not computed
13Data not computed