Properties

Label 18.0.295...643.2
Degree $18$
Signature $(0, 9)$
Discriminant $-2.954\times 10^{21}$
Root discriminant \(15.59\)
Ramified prime $3$
Class number $1$
Class group trivial
Galois group $C_9\times S_3$ (as 18T16)

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Normalized defining polynomial

Copy content comment:Define the number field
 
Copy content sage:x = polygen(QQ); K.<a> = NumberField(x^18 - 9*x^15 + 36*x^12 - 53*x^9 + 27*x^6 + 1)
 
Copy content gp:K = bnfinit(y^18 - 9*y^15 + 36*y^12 - 53*y^9 + 27*y^6 + 1, 1)
 
Copy content magma:R<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^18 - 9*x^15 + 36*x^12 - 53*x^9 + 27*x^6 + 1);
 
Copy content oscar:Qx, x = polynomial_ring(QQ); K, a = number_field(x^18 - 9*x^15 + 36*x^12 - 53*x^9 + 27*x^6 + 1)
 

\( x^{18} - 9x^{15} + 36x^{12} - 53x^{9} + 27x^{6} + 1 \) Copy content Toggle raw display

Copy content comment:Defining polynomial
 
Copy content sage:K.defining_polynomial()
 
Copy content gp:K.pol
 
Copy content magma:DefiningPolynomial(K);
 
Copy content oscar:defining_polynomial(K)
 

Invariants

Degree:  $18$
Copy content comment:Degree over Q
 
Copy content sage:K.degree()
 
Copy content gp:poldegree(K.pol)
 
Copy content magma:Degree(K);
 
Copy content oscar:degree(K)
 
Signature:  $(0, 9)$
Copy content comment:Signature
 
Copy content sage:K.signature()
 
Copy content gp:K.sign
 
Copy content magma:Signature(K);
 
Copy content oscar:signature(K)
 
Discriminant:   \(-2954312706550833698643\) \(\medspace = -\,3^{45}\) Copy content Toggle raw display
Copy content comment:Discriminant
 
Copy content sage:K.disc()
 
Copy content gp:K.disc
 
Copy content magma:OK := Integers(K); Discriminant(OK);
 
Copy content oscar:OK = ring_of_integers(K); discriminant(OK)
 
Root discriminant:  \(15.59\)
Copy content comment:Root discriminant
 
Copy content sage:(K.disc().abs())^(1./K.degree())
 
Copy content gp:abs(K.disc)^(1/poldegree(K.pol))
 
Copy content magma:Abs(Discriminant(OK))^(1/Degree(K));
 
Copy content oscar:OK = ring_of_integers(K); (1.0 * abs(discriminant(OK)))^(1/degree(K))
 
Galois root discriminant:  $3^{49/18}\approx 19.898946404249138$
Ramified primes:   \(3\) Copy content Toggle raw display
Copy content comment:Ramified primes
 
Copy content sage:K.disc().support()
 
Copy content gp:factor(abs(K.disc))[,1]~
 
Copy content magma:PrimeDivisors(Discriminant(OK));
 
Copy content oscar:prime_divisors(discriminant(OK))
 
Discriminant root field:  \(\Q(\sqrt{-3}) \)
$\Aut(K/\Q)$:   $C_9$
Copy content comment:Automorphisms
 
Copy content sage:K.automorphisms()
 
Copy content magma:Automorphisms(K);
 
Copy content oscar:automorphism_group(K)
 
This field is not Galois over $\Q$.
This is not a CM field.
Maximal CM subfield:  \(\Q(\zeta_{9})\)

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

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $\frac{1}{2071}a^{15}-\frac{393}{2071}a^{12}-\frac{235}{2071}a^{9}-\frac{937}{2071}a^{6}-\frac{519}{2071}a^{3}+\frac{480}{2071}$, $\frac{1}{2071}a^{16}-\frac{393}{2071}a^{13}-\frac{235}{2071}a^{10}-\frac{937}{2071}a^{7}-\frac{519}{2071}a^{4}+\frac{480}{2071}a$, $\frac{1}{2071}a^{17}-\frac{393}{2071}a^{14}-\frac{235}{2071}a^{11}-\frac{937}{2071}a^{8}-\frac{519}{2071}a^{5}+\frac{480}{2071}a^{2}$ Copy content Toggle raw display

Copy content comment:Integral basis
 
Copy content sage:K.integral_basis()
 
Copy content gp:K.zk
 
Copy content magma:IntegralBasis(K);
 
Copy content oscar:basis(OK)
 

Monogenic:  Not computed
Index:  $1$
Inessential primes:  None

Class group and class number

Ideal class group:  Trivial group, which has order $1$
Copy content comment:Class group
 
Copy content sage:K.class_group().invariants()
 
Copy content gp:K.clgp
 
Copy content magma:ClassGroup(K);
 
Copy content oscar:class_group(K)
 
Narrow class group:  Trivial group, which has order $1$
Copy content comment:Narrow class group
 
Copy content sage:K.narrow_class_group().invariants()
 
Copy content gp:bnfnarrow(K)
 
Copy content magma:NarrowClassGroup(K);
 

Unit group

Copy content comment:Unit group
 
Copy content sage:UK = K.unit_group()
 
Copy content magma:UK, fUK := UnitGroup(K);
 
Copy content oscar:UK, fUK = unit_group(OK)
 
Rank:  $8$
Copy content comment:Unit rank
 
Copy content sage:UK.rank()
 
Copy content gp:K.fu
 
Copy content magma:UnitRank(K);
 
Copy content oscar:rank(UK)
 
Torsion generator:   \( \frac{350}{2071} a^{15} - \frac{2935}{2071} a^{12} + \frac{10945}{2071} a^{9} - \frac{13158}{2071} a^{6} + \frac{6811}{2071} a^{3} - \frac{1822}{2071} \)  (order $18$) Copy content Toggle raw display
Copy content comment:Generator for roots of unity
 
Copy content sage:UK.torsion_generator()
 
Copy content gp:K.tu[2]
 
Copy content magma:K!f(TU.1) where TU,f is TorsionUnitGroup(K);
 
Copy content oscar:torsion_units_generator(OK)
 
Fundamental units:   $\frac{350}{2071}a^{16}-\frac{2935}{2071}a^{13}+\frac{10945}{2071}a^{10}-\frac{13158}{2071}a^{7}+\frac{6811}{2071}a^{4}-\frac{3893}{2071}a$, $\frac{6}{109}a^{16}-\frac{69}{109}a^{13}+\frac{334}{109}a^{10}-\frac{717}{109}a^{7}+\frac{483}{109}a^{4}+\frac{46}{109}a$, $\frac{6}{109}a^{17}-\frac{604}{2071}a^{16}-\frac{75}{2071}a^{15}-\frac{69}{109}a^{14}+\frac{5420}{2071}a^{13}+\frac{481}{2071}a^{12}+\frac{334}{109}a^{11}-\frac{21669}{2071}a^{10}-\frac{1014}{2071}a^{9}-\frac{717}{109}a^{8}+\frac{31630}{2071}a^{7}-\frac{2210}{2071}a^{6}+\frac{483}{109}a^{5}-\frac{15813}{2071}a^{4}+\frac{3718}{2071}a^{3}+\frac{46}{109}a^{2}+\frac{20}{2071}a-\frac{793}{2071}$, $\frac{975}{2071}a^{17}+\frac{726}{2071}a^{16}+\frac{451}{2071}a^{15}-\frac{8324}{2071}a^{14}-\frac{5733}{2071}a^{13}-\frac{3279}{2071}a^{12}+\frac{31821}{2071}a^{11}+\frac{19922}{2071}a^{10}+\frac{9991}{2071}a^{9}-\frac{41684}{2071}a^{8}-\frac{17542}{2071}a^{7}-\frac{2174}{2071}a^{6}+\frac{24151}{2071}a^{5}+\frac{4270}{2071}a^{4}-\frac{6259}{2071}a^{3}-\frac{6259}{2071}a^{2}-\frac{1519}{2071}a-\frac{975}{2071}$, $\frac{544}{2071}a^{17}+\frac{1418}{2071}a^{16}+\frac{275}{2071}a^{15}-\frac{4621}{2071}a^{14}-\frac{12601}{2071}a^{13}-\frac{2454}{2071}a^{12}+\frac{17130}{2071}a^{11}+\frac{49905}{2071}a^{10}+\frac{9931}{2071}a^{9}-\frac{18901}{2071}a^{8}-\frac{71569}{2071}a^{7}-\frac{15368}{2071}a^{6}-\frac{680}{2071}a^{5}+\frac{36541}{2071}a^{4}+\frac{10529}{2071}a^{3}+\frac{10529}{2071}a^{2}+\frac{1352}{2071}a-\frac{544}{2071}$, $\frac{653}{2071}a^{17}-\frac{303}{2071}a^{16}-\frac{425}{2071}a^{15}-\frac{6038}{2071}a^{14}+\frac{3103}{2071}a^{13}+\frac{3416}{2071}a^{12}+\frac{24651}{2071}a^{11}-\frac{13706}{2071}a^{10}-\frac{11959}{2071}a^{9}-\frac{38194}{2071}a^{8}+\frac{25036}{2071}a^{7}+\frac{10948}{2071}a^{6}+\frac{19376}{2071}a^{5}-\frac{12565}{2071}a^{4}-\frac{1022}{2071}a^{3}-\frac{1352}{2071}a^{2}-\frac{2541}{2071}a+\frac{1029}{2071}$, $\frac{140}{2071}a^{15}-\frac{1174}{2071}a^{12}+\frac{4378}{2071}a^{9}-\frac{4849}{2071}a^{6}-\frac{175}{2071}a^{3}-a^{2}-a+\frac{928}{2071}$, $\frac{6}{109}a^{17}-\frac{6}{109}a^{16}+\frac{140}{2071}a^{15}-\frac{69}{109}a^{14}+\frac{69}{109}a^{13}-\frac{1174}{2071}a^{12}+\frac{334}{109}a^{11}-\frac{334}{109}a^{10}+\frac{4378}{2071}a^{9}-\frac{717}{109}a^{8}+\frac{717}{109}a^{7}-\frac{4849}{2071}a^{6}+\frac{483}{109}a^{5}-\frac{483}{109}a^{4}-\frac{175}{2071}a^{3}+\frac{46}{109}a^{2}+\frac{63}{109}a+\frac{928}{2071}$ Copy content Toggle raw display
Copy content comment:Fundamental units
 
Copy content sage:UK.fundamental_units()
 
Copy content gp:K.fu
 
Copy content magma:[K|fUK(g): g in Generators(UK)];
 
Copy content oscar:[K(fUK(a)) for a in gens(UK)]
 
Regulator:  \( 23143.3269777 \)
Copy content comment:Regulator
 
Copy content sage:K.regulator()
 
Copy content gp:K.reg
 
Copy content magma:Regulator(K);
 
Copy content oscar:regulator(K)
 

Class number formula

\[ \begin{aligned}\lim_{s\to 1} (s-1)\zeta_K(s) =\mathstrut & \frac{2^{r_1}\cdot (2\pi)^{r_2}\cdot R\cdot h}{w\cdot\sqrt{|D|}}\cr \approx\mathstrut &\frac{2^{0}\cdot(2\pi)^{9}\cdot 23143.3269777 \cdot 1}{18\cdot\sqrt{2954312706550833698643}}\cr\approx \mathstrut & 0.361030481189 \end{aligned}\]

Copy content comment:Analytic class number formula
 
Copy content sage:# self-contained SageMath code snippet to compute the analytic class number formula x = polygen(QQ); K.<a> = NumberField(x^18 - 9*x^15 + 36*x^12 - 53*x^9 + 27*x^6 + 1) DK = K.disc(); r1,r2 = K.signature(); RK = K.regulator(); RR = RK.parent() hK = K.class_number(); wK = K.unit_group().torsion_generator().order(); 2^r1 * (2*RR(pi))^r2 * RK * hK / (wK * RR(sqrt(abs(DK))))
 
Copy content gp:\\ self-contained Pari/GP code snippet to compute the analytic class number formula K = bnfinit(x^18 - 9*x^15 + 36*x^12 - 53*x^9 + 27*x^6 + 1, 1); [polcoeff (lfunrootres (lfuncreate (K))[1][1][2], -1), 2^K.r1 * (2*Pi)^K.r2 * K.reg * K.no / (K.tu[1] * sqrt (abs (K.disc)))]
 
Copy content magma:/* self-contained Magma code snippet to compute the analytic class number formula */ Qx<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^18 - 9*x^15 + 36*x^12 - 53*x^9 + 27*x^6 + 1); OK := Integers(K); DK := Discriminant(OK); UK, fUK := UnitGroup(OK); clK, fclK := ClassGroup(OK); r1,r2 := Signature(K); RK := Regulator(K); RR := Parent(RK); hK := #clK; wK := #TorsionSubgroup(UK); 2^r1 * (2*Pi(RR))^r2 * RK * hK / (wK * Sqrt(RR!Abs(DK)));
 
Copy content oscar:# self-contained Oscar code snippet to compute the analytic class number formula Qx, x = polynomial_ring(QQ); K, a = number_field(x^18 - 9*x^15 + 36*x^12 - 53*x^9 + 27*x^6 + 1); OK = ring_of_integers(K); DK = discriminant(OK); UK, fUK = unit_group(OK); clK, fclK = class_group(OK); r1,r2 = signature(K); RK = regulator(K); RR = parent(RK); hK = order(clK); wK = torsion_units_order(K); 2^r1 * (2*pi)^r2 * RK * hK / (wK * sqrt(RR(abs(DK))))
 

Galois group

$S_3\times C_9$ (as 18T16):

Copy content comment:Galois group
 
Copy content sage:K.galois_group()
 
Copy content gp:polgalois(K.pol)
 
Copy content magma:G = GaloisGroup(K);
 
Copy content oscar:G, Gtx = galois_group(K); degree(K) > 1 ? (G, transitive_group_identification(G)) : (G, nothing)
 
A solvable group of order 54
The 27 conjugacy class representatives for $C_9\times S_3$
Character table for $C_9\times S_3$

Intermediate fields

\(\Q(\sqrt{-3}) \), \(\Q(\zeta_{9})^+\), \(\Q(\zeta_{9})\)

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

Copy content comment:Intermediate fields
 
Copy content sage:K.subfields()[1:-1]
 
Copy content gp:L = nfsubfields(K); L[2..length(L)]
 
Copy content magma:L := Subfields(K); L[2..#L];
 
Copy content oscar:subfields(K)[2:end-1]
 

Sibling fields

Degree 27 sibling: data not computed
Minimal sibling: This field is its own minimal sibling

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 $18$ ${\href{/padicField/7.9.0.1}{9} }^{2}$ $18$ ${\href{/padicField/13.9.0.1}{9} }^{2}$ ${\href{/padicField/17.6.0.1}{6} }^{3}$ ${\href{/padicField/19.3.0.1}{3} }^{3}{,}\,{\href{/padicField/19.1.0.1}{1} }^{9}$ $18$ $18$ ${\href{/padicField/31.9.0.1}{9} }^{2}$ ${\href{/padicField/37.3.0.1}{3} }^{3}{,}\,{\href{/padicField/37.1.0.1}{1} }^{9}$ $18$ ${\href{/padicField/43.9.0.1}{9} }^{2}$ $18$ ${\href{/padicField/53.2.0.1}{2} }^{9}$ $18$

In the table, R denotes a ramified prime. Cycle lengths which are repeated in a cycle type are indicated by exponents.

Copy content comment:Frobenius cycle types
 
Copy content sage:# to obtain a list of [e_i,f_i] for the factorization of the ideal pO_K for p=7 in Sage: p = 7; [(e, pr.norm().valuation(p)) for pr,e in K.factor(p)]
 
Copy content gp:\\ to obtain a list of [e_i,f_i] for the factorization of the ideal pO_K for p=7 in Pari: p = 7; pfac = idealprimedec(K, p); vector(length(pfac), j, [pfac[j][3], pfac[j][4]])
 
Copy content magma:// to obtain a list of [e_i,f_i] for the factorization of the ideal pO_K for p=7 in Magma: p := 7; [<pr[2], Valuation(Norm(pr[1]), p)> : pr in Factorization(p*Integers(K))];
 
Copy content oscar:# to obtain a list of [e_i,f_i] for the factorization of the ideal pO_K for p=7 in Oscar: p = 7; pfac = factor(ideal(ring_of_integers(K), p)); [(e, valuation(norm(pr),p)) for (pr,e) in pfac]
 

Local algebras for ramified primes

$p$LabelPolynomial $e$ $f$ $c$ Galois group Slope content
\(3\) Copy content Toggle raw display 3.1.18.45a2.44$x^{18} + 18 x^{17} + 18 x^{16} + 9 x^{14} + 9 x^{13} + 6 x^{12} + 18 x^{10} + 3$$18$$1$$45$not computednot computed

Artin representations

Label Dimension Conductor Artin stem field $G$ Ind $\chi(c)$
*54 1.1.1t1.a.a$1$ $1$ \(\Q\) $C_1$ $1$ $1$
*54 1.3.2t1.a.a$1$ $ 3 $ \(\Q(\sqrt{-3}) \) $C_2$ (as 2T1) $1$ $-1$
*54 1.9.3t1.a.a$1$ $ 3^{2}$ \(\Q(\zeta_{9})^+\) $C_3$ (as 3T1) $0$ $1$
*54 1.9.6t1.a.a$1$ $ 3^{2}$ \(\Q(\zeta_{9})\) $C_6$ (as 6T1) $0$ $-1$
*54 1.9.6t1.a.b$1$ $ 3^{2}$ \(\Q(\zeta_{9})\) $C_6$ (as 6T1) $0$ $-1$
*54 1.9.3t1.a.b$1$ $ 3^{2}$ \(\Q(\zeta_{9})^+\) $C_3$ (as 3T1) $0$ $1$
1.27.18t1.a.a$1$ $ 3^{3}$ \(\Q(\zeta_{27})\) $C_{18}$ (as 18T1) $0$ $-1$
1.27.18t1.a.b$1$ $ 3^{3}$ \(\Q(\zeta_{27})\) $C_{18}$ (as 18T1) $0$ $-1$
1.27.18t1.a.c$1$ $ 3^{3}$ \(\Q(\zeta_{27})\) $C_{18}$ (as 18T1) $0$ $-1$
1.27.9t1.a.a$1$ $ 3^{3}$ \(\Q(\zeta_{27})^+\) $C_9$ (as 9T1) $0$ $1$
1.27.18t1.a.d$1$ $ 3^{3}$ \(\Q(\zeta_{27})\) $C_{18}$ (as 18T1) $0$ $-1$
1.27.9t1.a.b$1$ $ 3^{3}$ \(\Q(\zeta_{27})^+\) $C_9$ (as 9T1) $0$ $1$
1.27.18t1.a.e$1$ $ 3^{3}$ \(\Q(\zeta_{27})\) $C_{18}$ (as 18T1) $0$ $-1$
1.27.9t1.a.c$1$ $ 3^{3}$ \(\Q(\zeta_{27})^+\) $C_9$ (as 9T1) $0$ $1$
1.27.9t1.a.d$1$ $ 3^{3}$ \(\Q(\zeta_{27})^+\) $C_9$ (as 9T1) $0$ $1$
1.27.9t1.a.e$1$ $ 3^{3}$ \(\Q(\zeta_{27})^+\) $C_9$ (as 9T1) $0$ $1$
1.27.9t1.a.f$1$ $ 3^{3}$ \(\Q(\zeta_{27})^+\) $C_9$ (as 9T1) $0$ $1$
1.27.18t1.a.f$1$ $ 3^{3}$ \(\Q(\zeta_{27})\) $C_{18}$ (as 18T1) $0$ $-1$
2.243.3t2.b.a$2$ $ 3^{5}$ 3.1.243.1 $S_3$ (as 3T2) $1$ $0$
2.243.6t5.b.a$2$ $ 3^{5}$ 6.0.177147.1 $S_3\times C_3$ (as 6T5) $0$ $0$
2.243.6t5.b.b$2$ $ 3^{5}$ 6.0.177147.1 $S_3\times C_3$ (as 6T5) $0$ $0$
*54 2.729.18t16.a.a$2$ $ 3^{6}$ 18.0.2954312706550833698643.2 $C_9\times S_3$ (as 18T16) $0$ $0$
*54 2.729.18t16.a.b$2$ $ 3^{6}$ 18.0.2954312706550833698643.2 $C_9\times S_3$ (as 18T16) $0$ $0$
*54 2.729.18t16.a.c$2$ $ 3^{6}$ 18.0.2954312706550833698643.2 $C_9\times S_3$ (as 18T16) $0$ $0$
*54 2.729.18t16.a.d$2$ $ 3^{6}$ 18.0.2954312706550833698643.2 $C_9\times S_3$ (as 18T16) $0$ $0$
*54 2.729.18t16.a.e$2$ $ 3^{6}$ 18.0.2954312706550833698643.2 $C_9\times S_3$ (as 18T16) $0$ $0$
*54 2.729.18t16.a.f$2$ $ 3^{6}$ 18.0.2954312706550833698643.2 $C_9\times S_3$ (as 18T16) $0$ $0$

Data is given for all irreducible representations of the Galois group for the Galois closure of this field. Those marked with * are summands in the permutation representation coming from this field. Representations which appear with multiplicity greater than one are indicated by exponents on the *.

Spectrum of ring of integers

(0)(0)(2)(3)(5)(7)(11)(13)(17)(19)(23)(29)(31)(37)(41)(43)(47)(53)(59)