Properties

Label 16.0.20462633487...0016.1
Degree $16$
Signature $[0, 8]$
Discriminant $2^{56}\cdot 7^{6}\cdot 17^{6}$
Root discriminant $67.91$
Ramified primes $2, 7, 17$
Class number $4$ (GRH)
Class group $[4]$ (GRH)
Galois group $C_2^2.C_2^2:D_4$ (as 16T225)

Related objects

Downloads

Learn more about

Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![54434884, 0, -58068192, 0, 24057244, 0, -5024112, 0, 624187, 0, -49008, 0, 2442, 0, -72, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^16 - 72*x^14 + 2442*x^12 - 49008*x^10 + 624187*x^8 - 5024112*x^6 + 24057244*x^4 - 58068192*x^2 + 54434884)
 
gp: K = bnfinit(x^16 - 72*x^14 + 2442*x^12 - 49008*x^10 + 624187*x^8 - 5024112*x^6 + 24057244*x^4 - 58068192*x^2 + 54434884, 1)
 

Normalized defining polynomial

\( x^{16} - 72 x^{14} + 2442 x^{12} - 49008 x^{10} + 624187 x^{8} - 5024112 x^{6} + 24057244 x^{4} - 58068192 x^{2} + 54434884 \)

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:  \(204626334874637321888403030016=2^{56}\cdot 7^{6}\cdot 17^{6}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $67.91$
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:  $2, 7, 17$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $\frac{1}{34} a^{12} - \frac{2}{17} a^{10} - \frac{3}{17} a^{8} - \frac{7}{17} a^{6} + \frac{15}{34} a^{4}$, $\frac{1}{68} a^{13} + \frac{15}{34} a^{11} + \frac{7}{17} a^{9} + \frac{5}{17} a^{7} + \frac{15}{68} a^{5} - \frac{1}{2} a^{3} - \frac{1}{2} a$, $\frac{1}{136327255418497921484} a^{14} - \frac{54048925607788920}{34081813854624480371} a^{12} - \frac{6558159790915094161}{34081813854624480371} a^{10} + \frac{10124861231722402212}{34081813854624480371} a^{8} + \frac{39190286969434416435}{136327255418497921484} a^{6} - \frac{4697707536310083264}{34081813854624480371} a^{4} + \frac{1453475172119534045}{4009625159367585926} a^{2} + \frac{110803116251468685}{286401797097684709}$, $\frac{1}{4226144917973435566004} a^{15} + \frac{9807867195987809135}{4226144917973435566004} a^{13} + \frac{750717273277694930581}{2113072458986717783002} a^{11} + \frac{421111440066899959627}{1056536229493358891501} a^{9} - \frac{2077891797176650952493}{4226144917973435566004} a^{7} + \frac{1631169922934521275493}{4226144917973435566004} a^{5} - \frac{16314169341252473163}{62149189970197581853} a^{3} - \frac{2928813535571594429}{17756911420056451958} a$

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

Class group and class number

$C_{4}$, which has order $4$ (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:  $7$
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:  \( 163331999.533 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$C_2^2.C_2^2:D_4$ (as 16T225):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A solvable group of order 128
The 32 conjugacy class representatives for $C_2^2.C_2^2:D_4$
Character table for $C_2^2.C_2^2:D_4$ is not computed

Intermediate fields

\(\Q(\sqrt{2}) \), 4.0.7168.1, 4.4.121856.1, 4.0.1088.2, 8.0.14848884736.9

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

Sibling fields

Degree 16 siblings: data not computed
Degree 32 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 ${\href{/LocalNumberField/3.8.0.1}{8} }^{2}$ ${\href{/LocalNumberField/5.4.0.1}{4} }^{4}$ R ${\href{/LocalNumberField/11.4.0.1}{4} }^{4}$ ${\href{/LocalNumberField/13.8.0.1}{8} }^{2}$ R ${\href{/LocalNumberField/19.2.0.1}{2} }^{8}$ ${\href{/LocalNumberField/23.4.0.1}{4} }^{2}{,}\,{\href{/LocalNumberField/23.2.0.1}{2} }^{2}{,}\,{\href{/LocalNumberField/23.1.0.1}{1} }^{4}$ ${\href{/LocalNumberField/29.8.0.1}{8} }^{2}$ ${\href{/LocalNumberField/31.4.0.1}{4} }^{2}{,}\,{\href{/LocalNumberField/31.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/37.8.0.1}{8} }^{2}$ ${\href{/LocalNumberField/41.4.0.1}{4} }^{2}{,}\,{\href{/LocalNumberField/41.2.0.1}{2} }^{4}$ ${\href{/LocalNumberField/43.8.0.1}{8} }^{2}$ ${\href{/LocalNumberField/47.2.0.1}{2} }^{4}{,}\,{\href{/LocalNumberField/47.1.0.1}{1} }^{8}$ ${\href{/LocalNumberField/53.4.0.1}{4} }^{4}$ ${\href{/LocalNumberField/59.2.0.1}{2} }^{8}$

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$2.8.28.74$x^{8} + 12 x^{4} + 28$$8$$1$$28$$Z_8 : Z_8^\times$$[2, 3, 7/2, 9/2]^{2}$
2.8.28.74$x^{8} + 12 x^{4} + 28$$8$$1$$28$$Z_8 : Z_8^\times$$[2, 3, 7/2, 9/2]^{2}$
$7$$\Q_{7}$$x + 2$$1$$1$$0$Trivial$[\ ]$
$\Q_{7}$$x + 2$$1$$1$$0$Trivial$[\ ]$
$\Q_{7}$$x + 2$$1$$1$$0$Trivial$[\ ]$
$\Q_{7}$$x + 2$$1$$1$$0$Trivial$[\ ]$
7.2.1.1$x^{2} - 7$$2$$1$$1$$C_2$$[\ ]_{2}$
7.2.1.1$x^{2} - 7$$2$$1$$1$$C_2$$[\ ]_{2}$
7.8.4.1$x^{8} + 14 x^{6} + 539 x^{4} + 343 x^{2} + 60025$$2$$4$$4$$C_4\times C_2$$[\ ]_{2}^{4}$
$17$17.4.0.1$x^{4} - x + 11$$1$$4$$0$$C_4$$[\ ]^{4}$
17.4.0.1$x^{4} - x + 11$$1$$4$$0$$C_4$$[\ ]^{4}$
17.8.6.2$x^{8} + 85 x^{4} + 2601$$4$$2$$6$$C_4\times C_2$$[\ ]_{4}^{2}$