Properties

Label 21.21.5116022582...2761.2
Degree $21$
Signature $[21, 0]$
Discriminant $7^{38}\cdot 13^{14}$
Root discriminant $187.01$
Ramified primes $7, 13$
Class number $3$ (GRH)
Class group $[3]$ (GRH)
Galois group $C_{21}$ (as 21T1)

Related objects

Downloads

Learn more about

Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![3691462039, 12876797381, -16933928459, -29178026367, 12754970620, 20583982601, -4423657378, -7150956164, 876942010, 1419969761, -106682856, -170719178, 7983444, 12591922, -347577, -559650, 7672, 14273, -63, -189, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^21 - 189*x^19 - 63*x^18 + 14273*x^17 + 7672*x^16 - 559650*x^15 - 347577*x^14 + 12591922*x^13 + 7983444*x^12 - 170719178*x^11 - 106682856*x^10 + 1419969761*x^9 + 876942010*x^8 - 7150956164*x^7 - 4423657378*x^6 + 20583982601*x^5 + 12754970620*x^4 - 29178026367*x^3 - 16933928459*x^2 + 12876797381*x + 3691462039)
 
gp: K = bnfinit(x^21 - 189*x^19 - 63*x^18 + 14273*x^17 + 7672*x^16 - 559650*x^15 - 347577*x^14 + 12591922*x^13 + 7983444*x^12 - 170719178*x^11 - 106682856*x^10 + 1419969761*x^9 + 876942010*x^8 - 7150956164*x^7 - 4423657378*x^6 + 20583982601*x^5 + 12754970620*x^4 - 29178026367*x^3 - 16933928459*x^2 + 12876797381*x + 3691462039, 1)
 

Normalized defining polynomial

\( x^{21} - 189 x^{19} - 63 x^{18} + 14273 x^{17} + 7672 x^{16} - 559650 x^{15} - 347577 x^{14} + 12591922 x^{13} + 7983444 x^{12} - 170719178 x^{11} - 106682856 x^{10} + 1419969761 x^{9} + 876942010 x^{8} - 7150956164 x^{7} - 4423657378 x^{6} + 20583982601 x^{5} + 12754970620 x^{4} - 29178026367 x^{3} - 16933928459 x^{2} + 12876797381 x + 3691462039 \)

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:  \(511602258272191839961280749067569616320187702761=7^{38}\cdot 13^{14}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $187.01$
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:  $7, 13$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is Galois and abelian over $\Q$.
Conductor:  \(637=7^{2}\cdot 13\)
Dirichlet character group:    $\lbrace$$\chi_{637}(256,·)$, $\chi_{637}(1,·)$, $\chi_{637}(198,·)$, $\chi_{637}(456,·)$, $\chi_{637}(74,·)$, $\chi_{637}(16,·)$, $\chi_{637}(529,·)$, $\chi_{637}(274,·)$, $\chi_{637}(471,·)$, $\chi_{637}(347,·)$, $\chi_{637}(92,·)$, $\chi_{637}(289,·)$, $\chi_{637}(547,·)$, $\chi_{637}(165,·)$, $\chi_{637}(107,·)$, $\chi_{637}(620,·)$, $\chi_{637}(365,·)$, $\chi_{637}(562,·)$, $\chi_{637}(438,·)$, $\chi_{637}(183,·)$, $\chi_{637}(380,·)$$\rbrace$
This is not a CM field.

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

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $a^{15}$, $a^{16}$, $a^{17}$, $a^{18}$, $a^{19}$, $\frac{1}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{20} - \frac{419842590607002008985991886153916636478208057306058380147646673092618533264278721169127849}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{19} - \frac{939961657360607987901323782225075386386197948405734489216403120849369276367845040752779700}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{18} + \frac{672221043756540786785053306726401847897574069131531709743973875599014900630936876419547887}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{17} - \frac{203336047035134500404934703205399157534175826838588518162176685150997672890841480393565040}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{16} - \frac{1781657319625941837124486998662787816336568200140309439419879993780837179394305188023262934}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{15} + \frac{655830512696693651972029065522693589463427147338223402152994137554888897246845016915127947}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{14} - \frac{1228199459110052858343563928937649667287944597177855210485465143831879814984702185025208854}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{13} + \frac{123524620186055035235425044406017657724139287414655346516452073533550281983484170548837635}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{12} + \frac{1127890542301323908697290232032422312295027454449941036135498474255521762182078569721127466}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{11} - \frac{420870233096743930238519787585850947195589442545616780147793402508023420852989956149162018}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{10} - \frac{1053142623616829067559033269194078561309287601899353118033611487520999025256017861395749237}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{9} + \frac{1694714318715807843165543878196844962896369853503674599026251444001963187603689389714275233}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{8} + \frac{1266553333879446873633486706990924285004089044701138450646925195400407884715629914054457527}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{7} - \frac{1785180878927276327777673141708034176060939639857043766771021054272391513953340835024346905}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{6} + \frac{458503782343717733373994459391505096151202580712229624461034514809337833379740654367612936}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{5} - \frac{817340110614819907556608317393059399423328374588915974819429897922288655873598832198319611}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{4} - \frac{366615502577909336627084255380619077001083877120117565153587077114125729935871108785447120}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{3} + \frac{776133983715866369798648301458297744036137732137386392201053710954005189622983581803782486}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a^{2} - \frac{1093460246756252525849988761700687687499183231673381302359956086648753681527628824394256735}{3870596894272440222805765367148971979858788123540698254867400616127258108798094342793330213} a + \frac{3375751958752329100161327739388148990891438785485222057373172995161530305839267778143097}{6802454998721336068199939133829476238767641693393142802930405300750892985585403062905677}$

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

Class group and class number

$C_{3}$, which has order $3$ (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:  \( 28334278031696510 \) (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

3.3.8281.1, 7.7.13841287201.1

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 ${\href{/LocalNumberField/2.7.0.1}{7} }^{3}$ $21$ $21$ R $21$ R ${\href{/LocalNumberField/17.7.0.1}{7} }^{3}$ ${\href{/LocalNumberField/19.3.0.1}{3} }^{7}$ ${\href{/LocalNumberField/23.7.0.1}{7} }^{3}$ $21$ ${\href{/LocalNumberField/31.3.0.1}{3} }^{7}$ ${\href{/LocalNumberField/37.7.0.1}{7} }^{3}$ $21$ $21$ $21$ $21$ ${\href{/LocalNumberField/59.7.0.1}{7} }^{3}$

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
13Data not computed