Properties

Label 21.21.6120466749...5121.1
Degree $21$
Signature $[21, 0]$
Discriminant $7^{14}\cdot 113^{18}$
Root discriminant $210.47$
Ramified primes $7, 113$
Class number $1$ (GRH)
Class group Trivial (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![1626227, -25278358, -3670640, 208339119, -52948234, -445036167, 170444833, 368567997, -176540462, -132545343, 79537118, 18143395, -16336335, 61944, 1418338, -145220, -51926, 7952, 792, -154, -4, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^21 - 4*x^20 - 154*x^19 + 792*x^18 + 7952*x^17 - 51926*x^16 - 145220*x^15 + 1418338*x^14 + 61944*x^13 - 16336335*x^12 + 18143395*x^11 + 79537118*x^10 - 132545343*x^9 - 176540462*x^8 + 368567997*x^7 + 170444833*x^6 - 445036167*x^5 - 52948234*x^4 + 208339119*x^3 - 3670640*x^2 - 25278358*x + 1626227)
 
gp: K = bnfinit(x^21 - 4*x^20 - 154*x^19 + 792*x^18 + 7952*x^17 - 51926*x^16 - 145220*x^15 + 1418338*x^14 + 61944*x^13 - 16336335*x^12 + 18143395*x^11 + 79537118*x^10 - 132545343*x^9 - 176540462*x^8 + 368567997*x^7 + 170444833*x^6 - 445036167*x^5 - 52948234*x^4 + 208339119*x^3 - 3670640*x^2 - 25278358*x + 1626227, 1)
 

Normalized defining polynomial

\( x^{21} - 4 x^{20} - 154 x^{19} + 792 x^{18} + 7952 x^{17} - 51926 x^{16} - 145220 x^{15} + 1418338 x^{14} + 61944 x^{13} - 16336335 x^{12} + 18143395 x^{11} + 79537118 x^{10} - 132545343 x^{9} - 176540462 x^{8} + 368567997 x^{7} + 170444833 x^{6} - 445036167 x^{5} - 52948234 x^{4} + 208339119 x^{3} - 3670640 x^{2} - 25278358 x + 1626227 \)

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:  \(6120466749549222213884941343724120599616956835121=7^{14}\cdot 113^{18}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $210.47$
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:  $7, 113$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is Galois and abelian over $\Q$.
Conductor:  \(791=7\cdot 113\)
Dirichlet character group:    $\lbrace$$\chi_{791}(256,·)$, $\chi_{791}(1,·)$, $\chi_{791}(708,·)$, $\chi_{791}(141,·)$, $\chi_{791}(16,·)$, $\chi_{791}(275,·)$, $\chi_{791}(340,·)$, $\chi_{791}(674,·)$, $\chi_{791}(219,·)$, $\chi_{791}(30,·)$, $\chi_{791}(480,·)$, $\chi_{791}(162,·)$, $\chi_{791}(242,·)$, $\chi_{791}(106,·)$, $\chi_{791}(109,·)$, $\chi_{791}(561,·)$, $\chi_{791}(114,·)$, $\chi_{791}(501,·)$, $\chi_{791}(694,·)$, $\chi_{791}(445,·)$, $\chi_{791}(254,·)$$\rbrace$
This is not a CM field.

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

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $a^{15}$, $a^{16}$, $a^{17}$, $\frac{1}{11461} a^{18} + \frac{4465}{11461} a^{17} + \frac{1853}{11461} a^{16} + \frac{5712}{11461} a^{15} - \frac{3147}{11461} a^{14} + \frac{1006}{11461} a^{13} + \frac{1938}{11461} a^{12} + \frac{1899}{11461} a^{11} + \frac{3053}{11461} a^{10} + \frac{1881}{11461} a^{9} + \frac{4206}{11461} a^{8} - \frac{41}{157} a^{7} + \frac{1594}{11461} a^{6} + \frac{4421}{11461} a^{5} + \frac{5059}{11461} a^{4} + \frac{2269}{11461} a^{3} - \frac{3539}{11461} a^{2} - \frac{64}{11461} a - \frac{2137}{11461}$, $\frac{1}{11461} a^{19} - \frac{3693}{11461} a^{17} - \frac{4552}{11461} a^{16} + \frac{4959}{11461} a^{15} + \frac{1175}{11461} a^{14} + \frac{2860}{11461} a^{13} + \frac{1784}{11461} a^{12} + \frac{5158}{11461} a^{11} - \frac{2635}{11461} a^{10} - \frac{5007}{11461} a^{9} + \frac{1796}{11461} a^{8} + \frac{1813}{11461} a^{7} + \frac{4492}{11461} a^{6} + \frac{1136}{11461} a^{5} + \frac{3465}{11461} a^{4} - \frac{3100}{11461} a^{3} - \frac{3148}{11461} a^{2} - \frac{2902}{11461} a - \frac{5308}{11461}$, $\frac{1}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{20} - \frac{6037327589845061997867535383739538486433916183117815888237635248762437}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{19} + \frac{196673616103622238538164811100981406097540241270409110343511959869156483}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{18} - \frac{2273122275889291841118995704844747254671682937890232495589775728257025722014}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{17} + \frac{1432094875715837450217524529852732558543085743579674596075526733351091961317}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{16} - \frac{624839482337881697442305708505444681353811226804360662883640323531960686338}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{15} - \frac{284614346563293770983624520307790119009047092442683817682498053942665513673}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{14} - \frac{895803626521815304328848478208357059391903338492786939379805863459935548297}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{13} - \frac{791535487902920207714081149101032051560581914145921235454802753545115595}{3652938187416791243177637289769478715901632151897596519915907779651346071} a^{12} + \frac{1891237267877341259076027712425002581799379854283894479761140805666979518342}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{11} + \frac{2647358339746681071227584100772750139798767450583285398458367759579008836647}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{10} - \frac{1504153376171812247968774654798129820707929729779097235936822332656670985962}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{9} + \frac{476288716608861900363322338349126027538117879027902958519356697033618161771}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{8} + \frac{1172034054077691259786192556169289163044855396814257857717454567602392363939}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{7} + \frac{2295682240005039558003651934233416908196246704067957075596716130433116770875}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{6} + \frac{26710503520058409033251690533046811596221491999097909248064403828358502150}{78413070406604272302182981274914700655039144959226489680934623160461086209} a^{5} - \frac{2139499642816029177909254565983755620633572417733335032995886422179409362934}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{4} - \frac{14642665757016624416944861254430540394056625109922229570173662895644109343}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{3} + \frac{602191377951273683073165683059009222805417027835423457139030845201737596728}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a^{2} + \frac{1775391190492677816649439148912312019466737712254162523820268359199049052478}{5724154139682111878059357633068773147817857582023533746708227490713659293257} a + \frac{846762154884790934626739454422323209710709572725866093368280572431789330155}{5724154139682111878059357633068773147817857582023533746708227490713659293257}$

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:  $20$
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:  \( 350292924482315400 \) (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

\(\Q(\zeta_{7})^+\), 7.7.2081951752609.1

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

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
$113$113.7.6.1$x^{7} - 113$$7$$1$$6$$C_7$$[\ ]_{7}$
113.7.6.1$x^{7} - 113$$7$$1$$6$$C_7$$[\ ]_{7}$
113.7.6.1$x^{7} - 113$$7$$1$$6$$C_7$$[\ ]_{7}$