Properties

Label 20.0.35120392099...0000.1
Degree $20$
Signature $[0, 10]$
Discriminant $2^{30}\cdot 5^{15}\cdot 41^{18}$
Root discriminant $267.47$
Ramified primes $2, 5, 41$
Class number $155042000$ (GRH)
Class group $[2, 10, 7752100]$ (GRH)
Galois group $C_{20}$ (as 20T1)

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![435715200000, 0, 2009131200000, 0, 2252271040000, 0, 642948880000, 0, 81710048000, 0, 5561404000, 0, 217300000, 0, 4936400, 0, 63140, 0, 410, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^20 + 410*x^18 + 63140*x^16 + 4936400*x^14 + 217300000*x^12 + 5561404000*x^10 + 81710048000*x^8 + 642948880000*x^6 + 2252271040000*x^4 + 2009131200000*x^2 + 435715200000)
 
gp: K = bnfinit(x^20 + 410*x^18 + 63140*x^16 + 4936400*x^14 + 217300000*x^12 + 5561404000*x^10 + 81710048000*x^8 + 642948880000*x^6 + 2252271040000*x^4 + 2009131200000*x^2 + 435715200000, 1)
 

Normalized defining polynomial

\( x^{20} + 410 x^{18} + 63140 x^{16} + 4936400 x^{14} + 217300000 x^{12} + 5561404000 x^{10} + 81710048000 x^{8} + 642948880000 x^{6} + 2252271040000 x^{4} + 2009131200000 x^{2} + 435715200000 \)

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

Invariants

Degree:  $20$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[0, 10]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(3512039209944081509788983935664128000000000000000=2^{30}\cdot 5^{15}\cdot 41^{18}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $267.47$
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:  $2, 5, 41$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is Galois and abelian over $\Q$.
Conductor:  \(1640=2^{3}\cdot 5\cdot 41\)
Dirichlet character group:    $\lbrace$$\chi_{1640}(1,·)$, $\chi_{1640}(277,·)$, $\chi_{1640}(517,·)$, $\chi_{1640}(961,·)$, $\chi_{1640}(1609,·)$, $\chi_{1640}(1281,·)$, $\chi_{1640}(1357,·)$, $\chi_{1640}(1041,·)$, $\chi_{1640}(1173,·)$, $\chi_{1640}(1369,·)$, $\chi_{1640}(201,·)$, $\chi_{1640}(329,·)$, $\chi_{1640}(933,·)$, $\chi_{1640}(1253,·)$, $\chi_{1640}(529,·)$, $\chi_{1640}(1557,·)$, $\chi_{1640}(373,·)$, $\chi_{1640}(1289,·)$, $\chi_{1640}(573,·)$, $\chi_{1640}(597,·)$$\rbrace$
This is a CM field.

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

$1$, $a$, $\frac{1}{2} a^{2}$, $\frac{1}{2} a^{3}$, $\frac{1}{20} a^{4}$, $\frac{1}{60} a^{5} - \frac{1}{6} a^{3} + \frac{1}{3} a$, $\frac{1}{120} a^{6} + \frac{1}{60} a^{4} + \frac{1}{6} a^{2}$, $\frac{1}{120} a^{7} - \frac{1}{6} a^{3} - \frac{1}{3} a$, $\frac{1}{1200} a^{8} - \frac{1}{60} a^{4} + \frac{1}{6} a^{2}$, $\frac{1}{1200} a^{9} + \frac{1}{3} a$, $\frac{1}{295200} a^{10} + \frac{1}{3600} a^{8} - \frac{1}{360} a^{6} - \frac{1}{90} a^{4} - \frac{1}{18} a^{2}$, $\frac{1}{295200} a^{11} + \frac{1}{3600} a^{9} - \frac{1}{360} a^{7} + \frac{1}{180} a^{5} - \frac{2}{9} a^{3} + \frac{1}{3} a$, $\frac{1}{2952000} a^{12} + \frac{1}{3600} a^{8} + \frac{1}{180} a^{4} - \frac{1}{9} a^{2}$, $\frac{1}{2952000} a^{13} + \frac{1}{3600} a^{9} + \frac{1}{180} a^{5} - \frac{1}{9} a^{3}$, $\frac{1}{5904000} a^{14} + \frac{1}{3600} a^{8} - \frac{1}{60} a^{4} - \frac{2}{9} a^{2}$, $\frac{1}{17712000} a^{15} + \frac{1}{2700} a^{9} + \frac{1}{180} a^{5} + \frac{4}{27} a^{3} - \frac{1}{3} a$, $\frac{1}{38789280000} a^{16} + \frac{19}{258595200} a^{14} + \frac{1}{7183200} a^{12} - \frac{91}{96973200} a^{10} + \frac{41}{131400} a^{8} - \frac{22}{9855} a^{6} - \frac{1537}{118260} a^{4} - \frac{116}{657} a^{2} + \frac{1}{73}$, $\frac{1}{38789280000} a^{17} + \frac{11}{646488000} a^{15} + \frac{1}{7183200} a^{13} - \frac{91}{96973200} a^{11} - \frac{23}{394200} a^{9} - \frac{22}{9855} a^{7} - \frac{223}{118260} a^{5} + \frac{17}{1971} a^{3} - \frac{70}{219} a$, $\frac{1}{248860167950024640000} a^{18} - \frac{68135969}{62215041987506160000} a^{16} + \frac{285408786601}{4147669465833744000} a^{14} + \frac{808739005031}{6221504198750616000} a^{12} + \frac{816730619333}{622150419875061600} a^{10} + \frac{103374920039}{632266686864900} a^{8} - \frac{1652338088623}{758720024237880} a^{6} + \frac{1756362346433}{75872002423788} a^{4} - \frac{157675620271}{4215111245766} a^{2} + \frac{62530036437}{234172846987}$, $\frac{1}{248860167950024640000} a^{19} - \frac{68135969}{62215041987506160000} a^{17} + \frac{8539323269}{691278244305624000} a^{15} + \frac{808739005031}{6221504198750616000} a^{13} + \frac{816730619333}{622150419875061600} a^{11} - \frac{32699481737}{158066671716225} a^{9} - \frac{1652338088623}{758720024237880} a^{7} + \frac{351589240633}{379360012118940} a^{5} - \frac{119427006913}{6322666868649} a^{3} + \frac{62530036437}{234172846987} a$

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

Class group and class number

$C_{2}\times C_{10}\times C_{7752100}$, which has order $155042000$ (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:  $9$
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:  \( 41023218.25673422 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$C_{20}$ (as 20T1):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A cyclic group of order 20
The 20 conjugacy class representatives for $C_{20}$
Character table for $C_{20}$

Intermediate fields

\(\Q(\sqrt{5}) \), 4.0.13448000.5, 5.5.2825761.1, 10.10.24952891341003125.1

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 R ${\href{/LocalNumberField/3.4.0.1}{4} }^{5}$ R $20$ ${\href{/LocalNumberField/11.5.0.1}{5} }^{4}$ $20$ $20$ ${\href{/LocalNumberField/19.10.0.1}{10} }^{2}$ $20$ ${\href{/LocalNumberField/29.10.0.1}{10} }^{2}$ ${\href{/LocalNumberField/31.5.0.1}{5} }^{4}$ $20$ R $20$ $20$ $20$ ${\href{/LocalNumberField/59.5.0.1}{5} }^{4}$

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
5Data not computed
$41$41.10.9.1$x^{10} - 41$$10$$1$$9$$C_{10}$$[\ ]_{10}$
41.10.9.1$x^{10} - 41$$10$$1$$9$$C_{10}$$[\ ]_{10}$