Properties

Label 21.21.1354455157...9961.1
Degree $21$
Signature $[21, 0]$
Discriminant $7^{14}\cdot 197^{18}$
Root discriminant $338.91$
Ramified primes $7, 197$
Class number $7$ (GRH)
Class group $[7]$ (GRH)
Galois group $C_{21}$ (as 21T1)

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![4073697629, -112640151504, -190583514332, 185139245847, 278406118274, -65958243269, -143924148549, -7081032431, 30745724450, 5552672841, -2979538158, -804361037, 131954593, 50774140, -2346530, -1645358, -1460, 28760, 498, -262, -4, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^21 - 4*x^20 - 262*x^19 + 498*x^18 + 28760*x^17 - 1460*x^16 - 1645358*x^15 - 2346530*x^14 + 50774140*x^13 + 131954593*x^12 - 804361037*x^11 - 2979538158*x^10 + 5552672841*x^9 + 30745724450*x^8 - 7081032431*x^7 - 143924148549*x^6 - 65958243269*x^5 + 278406118274*x^4 + 185139245847*x^3 - 190583514332*x^2 - 112640151504*x + 4073697629)
 
gp: K = bnfinit(x^21 - 4*x^20 - 262*x^19 + 498*x^18 + 28760*x^17 - 1460*x^16 - 1645358*x^15 - 2346530*x^14 + 50774140*x^13 + 131954593*x^12 - 804361037*x^11 - 2979538158*x^10 + 5552672841*x^9 + 30745724450*x^8 - 7081032431*x^7 - 143924148549*x^6 - 65958243269*x^5 + 278406118274*x^4 + 185139245847*x^3 - 190583514332*x^2 - 112640151504*x + 4073697629, 1)
 

Normalized defining polynomial

\( x^{21} - 4 x^{20} - 262 x^{19} + 498 x^{18} + 28760 x^{17} - 1460 x^{16} - 1645358 x^{15} - 2346530 x^{14} + 50774140 x^{13} + 131954593 x^{12} - 804361037 x^{11} - 2979538158 x^{10} + 5552672841 x^{9} + 30745724450 x^{8} - 7081032431 x^{7} - 143924148549 x^{6} - 65958243269 x^{5} + 278406118274 x^{4} + 185139245847 x^{3} - 190583514332 x^{2} - 112640151504 x + 4073697629 \)

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

Invariants

Degree:  $21$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[21, 0]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(135445515708155977295451660588195107344558789043889961=7^{14}\cdot 197^{18}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $338.91$
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:  $7, 197$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is Galois and abelian over $\Q$.
Conductor:  \(1379=7\cdot 197\)
Dirichlet character group:    $\lbrace$$\chi_{1379}(1,·)$, $\chi_{1379}(1346,·)$, $\chi_{1379}(198,·)$, $\chi_{1379}(1089,·)$, $\chi_{1379}(585,·)$, $\chi_{1379}(1163,·)$, $\chi_{1379}(695,·)$, $\chi_{1379}(1296,·)$, $\chi_{1379}(1360,·)$, $\chi_{1379}(1373,·)$, $\chi_{1379}(361,·)$, $\chi_{1379}(592,·)$, $\chi_{1379}(36,·)$, $\chi_{1379}(233,·)$, $\chi_{1379}(498,·)$, $\chi_{1379}(114,·)$, $\chi_{1379}(627,·)$, $\chi_{1379}(375,·)$, $\chi_{1379}(508,·)$, $\chi_{1379}(1149,·)$, $\chi_{1379}(191,·)$$\rbrace$
This is not a CM field.

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

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $a^{15}$, $a^{16}$, $\frac{1}{1021} a^{17} + \frac{180}{1021} a^{16} + \frac{291}{1021} a^{15} - \frac{65}{1021} a^{14} + \frac{173}{1021} a^{13} + \frac{459}{1021} a^{12} + \frac{455}{1021} a^{11} + \frac{233}{1021} a^{10} - \frac{233}{1021} a^{9} - \frac{489}{1021} a^{8} + \frac{206}{1021} a^{7} + \frac{425}{1021} a^{6} + \frac{360}{1021} a^{5} - \frac{5}{1021} a^{4} + \frac{245}{1021} a^{3} + \frac{379}{1021} a^{2} + \frac{473}{1021} a + \frac{213}{1021}$, $\frac{1}{1477387} a^{18} + \frac{170}{1477387} a^{17} + \frac{216985}{1477387} a^{16} - \frac{309275}{1477387} a^{15} - \frac{700604}{1477387} a^{14} - \frac{351474}{1477387} a^{13} + \frac{278682}{1477387} a^{12} - \frac{618959}{1477387} a^{11} + \frac{721326}{1477387} a^{10} - \frac{678145}{1477387} a^{9} + \frac{163351}{1477387} a^{8} + \frac{554810}{1477387} a^{7} - \frac{255056}{1477387} a^{6} + \frac{121978}{1477387} a^{5} + \frac{450556}{1477387} a^{4} + \frac{325670}{1477387} a^{3} - \frac{292260}{1477387} a^{2} - \frac{424148}{1477387} a - \frac{575932}{1477387}$, $\frac{1}{13856412673} a^{19} - \frac{2766}{13856412673} a^{18} + \frac{5552169}{13856412673} a^{17} + \frac{950566353}{13856412673} a^{16} - \frac{454555217}{13856412673} a^{15} - \frac{3514145808}{13856412673} a^{14} - \frac{6270238324}{13856412673} a^{13} + \frac{3290704228}{13856412673} a^{12} - \frac{735195905}{13856412673} a^{11} - \frac{6834113793}{13856412673} a^{10} - \frac{889904371}{13856412673} a^{9} + \frac{3063589941}{13856412673} a^{8} - \frac{414014109}{13856412673} a^{7} + \frac{2956706386}{13856412673} a^{6} + \frac{3515536988}{13856412673} a^{5} + \frac{6276070815}{13856412673} a^{4} + \frac{1911920038}{13856412673} a^{3} + \frac{2829515734}{13856412673} a^{2} + \frac{4107765478}{13856412673} a + \frac{5638738701}{13856412673}$, $\frac{1}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{20} + \frac{3036722973839359326338183300866297659337321225283615788636543698862416489}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{19} - \frac{29312369018111262399106993576503689069157258585261536561107409097730933656366}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{18} + \frac{67218987288090473600195547545899347006893210353619628011666694574275401978789645}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{17} + \frac{48356768902575190389431469243799062761934327327377666080842296313412404062186403447}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{16} - \frac{27781353913204427412525704790868879080633480039522162465755986035576222215947186265}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{15} + \frac{291888134824277907546672989811182682197751764845667303960392367386573316431736639}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{14} + \frac{60589891131337712761704687310193225424106356744276763171888555007611266165674826137}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{13} - \frac{61508012622544608822980393289505053162412313254597615135128813192692226518303534871}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{12} + \frac{33743731382975850903248600459062818068468711335241290412868497724989065564375505763}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{11} + \frac{17785819700443874866439779441657560072663872376345485092328876312194551456969277602}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{10} - \frac{23183426607791060872525247402407253768671514746807697583374432886353529177197764890}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{9} - \frac{5412101502979367650977833825301390300282291995029350668949459662267509776184644593}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{8} - \frac{27550622810949643749275345175187810148081968721132896690078618992693046288930862273}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{7} + \frac{37101770606071890706886989936867648774212231956428491597177223575151652206608193215}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{6} + \frac{46220753219528106809654611750766421969884751085099255008069612323949674494392374174}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{5} - \frac{24992935352335686602208439604930089999818220800276447518825704501539652806770668034}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{4} + \frac{50482075076381968118147465609709409763001151906727972585915390963029567719585365692}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{3} + \frac{3131809299154489300405619098193951091259444532745245100692455905988552204452397157}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a^{2} + \frac{73361128450657621683481575177228232729936092198892957725142175543679716342968523323}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643} a - \frac{23244408581579810534879724087371033658333478096817417462219710886074837780550291590}{153049134962093675124438537545344054378198542776402202824101935183974334717306525643}$

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

Class group and class number

$C_{7}$, which has order $7$ (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:  $20$
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:  \( 9941186336646355000 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$C_{21}$ (as 21T1):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
A cyclic group of order 21
The 21 conjugacy class representatives for $C_{21}$
Character table for $C_{21}$ is not computed

Intermediate fields

\(\Q(\zeta_{7})^+\), 7.7.58451728309129.1

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 $21$ $21$ $21$ R $21$ ${\href{/LocalNumberField/13.7.0.1}{7} }^{3}$ $21$ ${\href{/LocalNumberField/19.3.0.1}{3} }^{7}$ $21$ ${\href{/LocalNumberField/29.7.0.1}{7} }^{3}$ $21$ $21$ ${\href{/LocalNumberField/41.7.0.1}{7} }^{3}$ ${\href{/LocalNumberField/43.7.0.1}{7} }^{3}$ $21$ $21$ $21$

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
7Data not computed
$197$197.7.6.1$x^{7} - 197$$7$$1$$6$$C_7$$[\ ]_{7}$
197.7.6.1$x^{7} - 197$$7$$1$$6$$C_7$$[\ ]_{7}$
197.7.6.1$x^{7} - 197$$7$$1$$6$$C_7$$[\ ]_{7}$