↑

Properties

Label 16.0.25991671039...696.11
Degree $16$
Signature $[0, 8]$
Discriminant $2^{36}\cdot 3^{8}\cdot 7^{8}$
Root discriminant $21.80$
Ramified primes $2, 3, 7$
Class number $4$
Class group $[2, 2]$
Galois group $C_2^2 \times D_4$ (as 16T25)

Related objects

Downloads

Learn more about

Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![324, 0, -216, 0, -36, 0, 480, 0, -35, 0, -156, 0, 74, 0, -12, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^16 - 12*x^14 + 74*x^12 - 156*x^10 - 35*x^8 + 480*x^6 - 36*x^4 - 216*x^2 + 324)
 
gp: K = bnfinit(x^16 - 12*x^14 + 74*x^12 - 156*x^10 - 35*x^8 + 480*x^6 - 36*x^4 - 216*x^2 + 324, 1)
 

Normalized defining polynomial

\( x^{16} - 12 x^{14} + 74 x^{12} - 156 x^{10} - 35 x^{8} + 480 x^{6} - 36 x^{4} - 216 x^{2} + 324 \)

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

Invariants

Degree:  $16$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[0, 8]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(2599167103947239325696=2^{36}\cdot 3^{8}\cdot 7^{8}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $21.80$
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:  $2, 3, 7$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $\frac{1}{2} a^{7} - \frac{1}{2} a^{6} - \frac{1}{2} a^{5} - \frac{1}{2} a^{4}$, $\frac{1}{2} a^{8} - \frac{1}{2} a^{4}$, $\frac{1}{2} a^{9} - \frac{1}{2} a^{5}$, $\frac{1}{12} a^{10} - \frac{1}{4} a^{8} - \frac{1}{12} a^{6} - \frac{1}{2} a^{5} + \frac{1}{4} a^{4} - \frac{1}{2} a^{3} - \frac{1}{6} a^{2} - \frac{1}{2}$, $\frac{1}{12} a^{11} - \frac{1}{4} a^{9} - \frac{1}{12} a^{7} - \frac{1}{2} a^{6} + \frac{1}{4} a^{5} - \frac{1}{2} a^{4} - \frac{1}{6} a^{3} - \frac{1}{2} a$, $\frac{1}{36} a^{12} + \frac{1}{18} a^{8} - \frac{1}{6} a^{6} - \frac{1}{2} a^{5} + \frac{1}{36} a^{4} - \frac{1}{2} a^{3} - \frac{1}{3} a^{2} - \frac{1}{2}$, $\frac{1}{36} a^{13} + \frac{1}{18} a^{9} - \frac{1}{6} a^{7} - \frac{1}{2} a^{6} + \frac{1}{36} a^{5} - \frac{1}{2} a^{4} - \frac{1}{3} a^{3} - \frac{1}{2} a$, $\frac{1}{1107827604} a^{14} + \frac{138208}{30772989} a^{12} + \frac{12452545}{553913802} a^{10} - \frac{37906129}{184637934} a^{8} + \frac{439707043}{1107827604} a^{6} - \frac{81008885}{184637934} a^{4} + \frac{3233081}{61545978} a^{2} - \frac{2701399}{10257663}$, $\frac{1}{1107827604} a^{15} + \frac{138208}{30772989} a^{13} + \frac{12452545}{553913802} a^{11} - \frac{37906129}{184637934} a^{9} - \frac{114206759}{1107827604} a^{7} - \frac{1}{2} a^{6} + \frac{5655041}{92318967} a^{5} - \frac{1}{2} a^{4} + \frac{3233081}{61545978} a^{3} - \frac{2701399}{10257663} a$

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

Class group and class number

$C_{2}\times C_{2}$, which has order $4$

magma: ClassGroup(K);
 
sage: K.class_group().invariants()
 
gp: K.clgp
 

Unit group

magma: UK, f := UnitGroup(K);
 
sage: UK = K.unit_group()
 
Rank:  $7$
magma: UnitRank(K);
 
sage: UK.rank()
 
gp: K.fu
 
Torsion generator:  \( \frac{212}{195453} a^{14} - \frac{155}{14478} a^{12} + \frac{18929}{390906} a^{10} + \frac{2840}{65151} a^{8} - \frac{250217}{390906} a^{6} + \frac{107021}{130302} a^{4} + \frac{20348}{21717} a^{2} - \frac{4802}{7239} \) (order $4$)
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
magma: [K!f(g): g in Generators(UK)];
 
sage: UK.fundamental_units()
 
gp: K.fu
 
Regulator:  \( 25816.0461632 \)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$C_2^2\times D_4$ (as 16T25):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A solvable group of order 32
The 20 conjugacy class representatives for $C_2^2 \times D_4$
Character table for $C_2^2 \times D_4$

Intermediate fields

\(\Q(\sqrt{-1}) \), \(\Q(\sqrt{-6}) \), \(\Q(\sqrt{7}) \), \(\Q(\sqrt{42}) \), \(\Q(\sqrt{6}) \), \(\Q(\sqrt{-7}) \), \(\Q(\sqrt{-42}) \), 4.2.37632.1, 4.2.9408.2, 4.2.37632.2, 4.2.9408.1, \(\Q(\sqrt{6}, \sqrt{-7})\), \(\Q(i, \sqrt{6})\), \(\Q(\sqrt{6}, \sqrt{7})\), \(\Q(i, \sqrt{7})\), \(\Q(\sqrt{-6}, \sqrt{-7})\), \(\Q(i, \sqrt{42})\), \(\Q(\sqrt{-6}, \sqrt{7})\), 8.0.12745506816.7, 8.4.50982027264.2, 8.4.50982027264.1, 8.0.1416167424.1, 8.0.88510464.1, 8.0.50982027264.1, 8.0.50982027264.2

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 16 siblings: 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 ${\href{/LocalNumberField/5.4.0.1}{4} }^{4}$ R ${\href{/LocalNumberField/11.4.0.1}{4} }^{4}$ ${\href{/LocalNumberField/13.2.0.1}{2} }^{8}$ ${\href{/LocalNumberField/17.4.0.1}{4} }^{4}$ ${\href{/LocalNumberField/19.2.0.1}{2} }^{8}$ ${\href{/LocalNumberField/23.4.0.1}{4} }^{4}$ ${\href{/LocalNumberField/29.2.0.1}{2} }^{4}{,}\,{\href{/LocalNumberField/29.1.0.1}{1} }^{8}$ ${\href{/LocalNumberField/31.2.0.1}{2} }^{8}$ ${\href{/LocalNumberField/37.2.0.1}{2} }^{8}$ ${\href{/LocalNumberField/41.4.0.1}{4} }^{4}$ ${\href{/LocalNumberField/43.2.0.1}{2} }^{8}$ ${\href{/LocalNumberField/47.2.0.1}{2} }^{8}$ ${\href{/LocalNumberField/53.2.0.1}{2} }^{4}{,}\,{\href{/LocalNumberField/53.1.0.1}{1} }^{8}$ ${\href{/LocalNumberField/59.2.0.1}{2} }^{8}$

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
$2$2.8.18.55$x^{8} + 2 x^{6} + 4 x^{3} + 10$$8$$1$$18$$D_4\times C_2$$[2, 2, 3]^{2}$
2.8.18.55$x^{8} + 2 x^{6} + 4 x^{3} + 10$$8$$1$$18$$D_4\times C_2$$[2, 2, 3]^{2}$
$3$3.4.2.1$x^{4} + 9 x^{2} + 36$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
3.4.2.1$x^{4} + 9 x^{2} + 36$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
3.4.2.1$x^{4} + 9 x^{2} + 36$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
3.4.2.1$x^{4} + 9 x^{2} + 36$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
$7$7.4.2.1$x^{4} + 35 x^{2} + 441$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
7.4.2.1$x^{4} + 35 x^{2} + 441$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
7.4.2.1$x^{4} + 35 x^{2} + 441$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$
7.4.2.1$x^{4} + 35 x^{2} + 441$$2$$2$$2$$C_2^2$$[\ ]_{2}^{2}$