Properties

Label 20.4.13806701996...0000.1
Degree $20$
Signature $[4, 8]$
Discriminant $2^{20}\cdot 5^{16}\cdot 29^{15}$
Root discriminant $90.57$
Ramified primes $2, 5, 29$
Class number $1$ (GRH)
Class group Trivial (GRH)
Galois group $C_5:D_5.Q_8$ (as 20T105)

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![512778725, 0, -512778725, 0, 88410125, 0, -21218430, 0, 3658350, 0, -48778, 0, -54665, 0, 0, 0, 1450, 0, 0, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^20 + 1450*x^16 - 54665*x^12 - 48778*x^10 + 3658350*x^8 - 21218430*x^6 + 88410125*x^4 - 512778725*x^2 + 512778725)
 
gp: K = bnfinit(x^20 + 1450*x^16 - 54665*x^12 - 48778*x^10 + 3658350*x^8 - 21218430*x^6 + 88410125*x^4 - 512778725*x^2 + 512778725, 1)
 

Normalized defining polynomial

\( x^{20} + 1450 x^{16} - 54665 x^{12} - 48778 x^{10} + 3658350 x^{8} - 21218430 x^{6} + 88410125 x^{4} - 512778725 x^{2} + 512778725 \)

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

Invariants

Degree:  $20$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[4, 8]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(1380670199615709510551840000000000000000=2^{20}\cdot 5^{16}\cdot 29^{15}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $90.57$
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:  $2, 5, 29$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $\frac{1}{29} a^{4}$, $\frac{1}{29} a^{5}$, $\frac{1}{29} a^{6}$, $\frac{1}{29} a^{7}$, $\frac{1}{841} a^{8}$, $\frac{1}{841} a^{9}$, $\frac{1}{841} a^{10}$, $\frac{1}{841} a^{11}$, $\frac{1}{24389} a^{12}$, $\frac{1}{121945} a^{13} + \frac{2}{4205} a^{11} + \frac{1}{4205} a^{9} + \frac{2}{145} a^{7} + \frac{1}{145} a^{5}$, $\frac{1}{121945} a^{14} - \frac{2}{121945} a^{12} + \frac{1}{4205} a^{10} - \frac{2}{4205} a^{8} + \frac{1}{145} a^{6}$, $\frac{1}{121945} a^{15} + \frac{2}{145} a^{5}$, $\frac{1}{67191695} a^{16} - \frac{6}{2316955} a^{14} + \frac{2}{2316955} a^{12} + \frac{4}{79895} a^{10} - \frac{2}{4205} a^{8} - \frac{2}{145} a^{6} - \frac{8}{551} a^{4} + \frac{4}{19} a^{2} + \frac{9}{19}$, $\frac{1}{67191695} a^{17} - \frac{6}{2316955} a^{15} + \frac{2}{2316955} a^{13} + \frac{4}{79895} a^{11} - \frac{2}{4205} a^{9} - \frac{2}{145} a^{7} - \frac{8}{551} a^{5} + \frac{4}{19} a^{3} + \frac{9}{19} a$, $\frac{1}{71164287309930783205} a^{18} + \frac{179970998024}{71164287309930783205} a^{16} + \frac{2885350193723}{2453940941721751145} a^{14} - \frac{15878390771761}{2453940941721751145} a^{12} - \frac{46352168555802}{84618653162819005} a^{10} + \frac{183712021719}{4453613324358895} a^{8} + \frac{7844505652233}{583576918364269} a^{6} - \frac{5552359185467}{583576918364269} a^{4} + \frac{9526849369643}{20123342012561} a^{2} + \frac{980489047054}{20123342012561}$, $\frac{1}{71164287309930783205} a^{19} + \frac{179970998024}{71164287309930783205} a^{17} + \frac{2885350193723}{2453940941721751145} a^{15} + \frac{848990248160}{490788188344350229} a^{13} - \frac{1221096906136}{16923730632563801} a^{11} + \frac{1242835285538}{4453613324358895} a^{9} - \frac{21147497776518}{2917884591821345} a^{7} - \frac{7638453914774}{2917884591821345} a^{5} + \frac{9526849369643}{20123342012561} a^{3} + \frac{980489047054}{20123342012561} a$

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:  $11$
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:  \( 331243139693 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$C_5:D_5.Q_8$ (as 20T105):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A solvable group of order 400
The 28 conjugacy class representatives for $C_5:D_5.Q_8$
Character table for $C_5:D_5.Q_8$ is not computed

Intermediate fields

\(\Q(\sqrt{29}) \), 4.4.390224.1, 10.2.8012167578125.1

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

Sibling fields

Degree 20 sibling: data not computed
Degree 40 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 $20$ R ${\href{/LocalNumberField/7.4.0.1}{4} }^{4}{,}\,{\href{/LocalNumberField/7.2.0.1}{2} }^{2}$ $20$ ${\href{/LocalNumberField/13.4.0.1}{4} }^{4}{,}\,{\href{/LocalNumberField/13.2.0.1}{2} }^{2}$ $20$ ${\href{/LocalNumberField/19.4.0.1}{4} }^{5}$ ${\href{/LocalNumberField/23.4.0.1}{4} }^{4}{,}\,{\href{/LocalNumberField/23.2.0.1}{2} }^{2}$ R $20$ ${\href{/LocalNumberField/37.4.0.1}{4} }^{5}$ $20$ $20$ $20$ ${\href{/LocalNumberField/53.4.0.1}{4} }^{4}{,}\,{\href{/LocalNumberField/53.1.0.1}{1} }^{4}$ ${\href{/LocalNumberField/59.10.0.1}{10} }{,}\,{\href{/LocalNumberField/59.2.0.1}{2} }^{5}$

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
$5$5.2.0.1$x^{2} - x + 2$$1$$2$$0$$C_2$$[\ ]^{2}$
5.8.6.1$x^{8} - 5 x^{4} + 400$$4$$2$$6$$C_4\times C_2$$[\ ]_{4}^{2}$
5.10.10.10$x^{10} + 10 x^{8} + 5 x^{6} + 10 x^{5} - 20 x^{4} - 20 x^{2} + 2$$5$$2$$10$$F_{5}\times C_2$$[5/4]_{4}^{2}$
29Data not computed