Properties

Label 20.0.849...888.1
Degree $20$
Signature $[0, 10]$
Discriminant $8.495\times 10^{25}$
Root discriminant \(19.79\)
Ramified primes $2,11$
Class number $1$ (GRH)
Class group trivial (GRH)
Galois group $C_{10}\wr C_2$ (as 20T53)

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Show commands: Magma / Oscar / PariGP / SageMath

Normalized defining polynomial

sage: x = polygen(QQ); K.<a> = NumberField(x^20 - 4*x^18 + 18*x^16 - 40*x^14 + 92*x^12 - 160*x^10 + 352*x^8 - 352*x^6 + 528*x^4 - 704*x^2 + 352)
 
gp: K = bnfinit(y^20 - 4*y^18 + 18*y^16 - 40*y^14 + 92*y^12 - 160*y^10 + 352*y^8 - 352*y^6 + 528*y^4 - 704*y^2 + 352, 1)
 
magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^20 - 4*x^18 + 18*x^16 - 40*x^14 + 92*x^12 - 160*x^10 + 352*x^8 - 352*x^6 + 528*x^4 - 704*x^2 + 352);
 
oscar: Qx, x = PolynomialRing(QQ); K, a = NumberField(x^20 - 4*x^18 + 18*x^16 - 40*x^14 + 92*x^12 - 160*x^10 + 352*x^8 - 352*x^6 + 528*x^4 - 704*x^2 + 352)
 

\( x^{20} - 4x^{18} + 18x^{16} - 40x^{14} + 92x^{12} - 160x^{10} + 352x^{8} - 352x^{6} + 528x^{4} - 704x^{2} + 352 \) Copy content Toggle raw display

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

Invariants

Degree:  $20$
sage: K.degree()
 
gp: poldegree(K.pol)
 
magma: Degree(K);
 
oscar: degree(K)
 
Signature:  $[0, 10]$
sage: K.signature()
 
gp: K.sign
 
magma: Signature(K);
 
oscar: signature(K)
 
Discriminant:   \(84954018740373771557797888\) \(\medspace = 2^{55}\cdot 11^{9}\) Copy content Toggle raw display
sage: K.disc()
 
gp: K.disc
 
magma: OK := Integers(K); Discriminant(OK);
 
oscar: OK = ring_of_integers(K); discriminant(OK)
 
Root discriminant:  \(19.79\)
sage: (K.disc().abs())^(1./K.degree())
 
gp: abs(K.disc)^(1/poldegree(K.pol))
 
magma: Abs(Discriminant(OK))^(1/Degree(K));
 
oscar: (1.0 * dK)^(1/degree(K))
 
Galois root discriminant:  $2^{11/4}11^{9/10}\approx 58.22183708777889$
Ramified primes:   \(2\), \(11\) Copy content Toggle raw display
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
magma: PrimeDivisors(Discriminant(OK));
 
oscar: prime_divisors(discriminant((OK)))
 
Discriminant root field:  \(\Q(\sqrt{22}) \)
$\card{ \Aut(K/\Q) }$:  $10$
sage: K.automorphisms()
 
magma: Automorphisms(K);
 
oscar: automorphisms(K)
 
This field is not Galois over $\Q$.
This is not a CM field.

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

$1$, $a$, $a^{2}$, $a^{3}$, $\frac{1}{2}a^{4}$, $\frac{1}{2}a^{5}$, $\frac{1}{2}a^{6}$, $\frac{1}{2}a^{7}$, $\frac{1}{4}a^{8}$, $\frac{1}{4}a^{9}$, $\frac{1}{4}a^{10}$, $\frac{1}{4}a^{11}$, $\frac{1}{8}a^{12}$, $\frac{1}{8}a^{13}$, $\frac{1}{8}a^{14}$, $\frac{1}{8}a^{15}$, $\frac{1}{16}a^{16}$, $\frac{1}{16}a^{17}$, $\frac{1}{321989456}a^{18}+\frac{837739}{80497364}a^{16}-\frac{1251545}{20124341}a^{14}+\frac{854403}{80497364}a^{12}+\frac{203587}{40248682}a^{10}-\frac{1633200}{20124341}a^{8}-\frac{7047079}{40248682}a^{6}+\frac{5489405}{40248682}a^{4}+\frac{970885}{20124341}a^{2}-\frac{4788209}{20124341}$, $\frac{1}{321989456}a^{19}+\frac{837739}{80497364}a^{17}-\frac{1251545}{20124341}a^{15}+\frac{854403}{80497364}a^{13}+\frac{203587}{40248682}a^{11}-\frac{1633200}{20124341}a^{9}-\frac{7047079}{40248682}a^{7}+\frac{5489405}{40248682}a^{5}+\frac{970885}{20124341}a^{3}-\frac{4788209}{20124341}a$ Copy content Toggle raw display

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

Monogenic:  Not computed
Index:  $1$
Inessential primes:  None

Class group and class number

Trivial group, which has order $1$ (assuming GRH)

sage: K.class_group().invariants()
 
gp: K.clgp
 
magma: ClassGroup(K);
 
oscar: class_group(K)
 

Unit group

sage: UK = K.unit_group()
 
magma: UK, fUK := UnitGroup(K);
 
oscar: UK, fUK = unit_group(OK)
 
Rank:  $9$
sage: UK.rank()
 
gp: K.fu
 
magma: UnitRank(K);
 
oscar: rank(UK)
 
Torsion generator:   \( -1 \)  (order $2$) Copy content Toggle raw display
sage: UK.torsion_generator()
 
gp: K.tu[2]
 
magma: K!f(TU.1) where TU,f is TorsionUnitGroup(K);
 
oscar: torsion_units_generator(OK)
 
Fundamental units:   $\frac{2651761}{321989456}a^{18}-\frac{2145929}{80497364}a^{16}+\frac{9776739}{80497364}a^{14}-\frac{32631263}{160994728}a^{12}+\frac{37114423}{80497364}a^{10}-\frac{49414203}{80497364}a^{8}+\frac{36214365}{20124341}a^{6}-\frac{29980689}{40248682}a^{4}+\frac{48034355}{20124341}a^{2}-\frac{54921555}{20124341}$, $\frac{1465}{321989456}a^{18}-\frac{148583}{40248682}a^{16}+\frac{2537189}{160994728}a^{14}-\frac{12141835}{160994728}a^{12}+\frac{12904021}{80497364}a^{10}-\frac{15807183}{40248682}a^{8}+\frac{19940539}{40248682}a^{6}-\frac{48006757}{40248682}a^{4}+\frac{13642655}{20124341}a^{2}-\frac{31579858}{20124341}$, $\frac{1170421}{321989456}a^{18}-\frac{1772507}{160994728}a^{16}+\frac{4550757}{80497364}a^{14}-\frac{7539309}{80497364}a^{12}+\frac{10302687}{40248682}a^{10}-\frac{23816237}{80497364}a^{8}+\frac{32654637}{40248682}a^{6}-\frac{1171248}{20124341}a^{4}+\frac{23278020}{20124341}a^{2}-\frac{14008650}{20124341}$, $\frac{988555}{321989456}a^{18}-\frac{3090407}{321989456}a^{16}+\frac{6218571}{160994728}a^{14}-\frac{8592551}{160994728}a^{12}+\frac{6949229}{80497364}a^{10}-\frac{5165527}{40248682}a^{8}+\frac{17943125}{40248682}a^{6}-\frac{5081949}{20124341}a^{4}+\frac{3150203}{20124341}a^{2}-\frac{22074408}{20124341}$, $\frac{1210631}{160994728}a^{19}-\frac{1787851}{321989456}a^{18}-\frac{8258839}{321989456}a^{17}+\frac{392509}{20124341}a^{16}+\frac{19219579}{160994728}a^{15}-\frac{13605481}{160994728}a^{14}-\frac{37103405}{160994728}a^{13}+\frac{12969993}{80497364}a^{12}+\frac{43841021}{80497364}a^{11}-\frac{14390211}{40248682}a^{10}-\frac{69486669}{80497364}a^{9}+\frac{48853607}{80497364}a^{8}+\frac{40453668}{20124341}a^{7}-\frac{29279809}{20124341}a^{6}-\frac{54652091}{40248682}a^{5}+\frac{40648907}{40248682}a^{4}+\frac{62809001}{20124341}a^{3}-\frac{33058203}{20124341}a^{2}-\frac{76893068}{20124341}a+\frac{51701256}{20124341}$, $\frac{257815}{80497364}a^{19}+\frac{540037}{321989456}a^{18}-\frac{2351639}{160994728}a^{17}-\frac{890371}{321989456}a^{16}+\frac{5128999}{80497364}a^{15}+\frac{1665621}{80497364}a^{14}-\frac{3127141}{20124341}a^{13}-\frac{1657537}{80497364}a^{12}+\frac{7002154}{20124341}a^{11}+\frac{2618918}{20124341}a^{10}-\frac{50064453}{80497364}a^{9}-\frac{15865913}{80497364}a^{8}+\frac{26039213}{20124341}a^{7}+\frac{30724587}{40248682}a^{6}-\frac{26910182}{20124341}a^{5}-\frac{7370192}{20124341}a^{4}+\frac{28776009}{20124341}a^{3}+\frac{34491013}{20124341}a^{2}-\frac{39235193}{20124341}a-\frac{13324302}{20124341}$, $\frac{988555}{321989456}a^{19}-\frac{5530}{20124341}a^{18}-\frac{3090407}{321989456}a^{17}-\frac{670927}{321989456}a^{16}+\frac{6218571}{160994728}a^{15}-\frac{2361}{160994728}a^{14}-\frac{8592551}{160994728}a^{13}-\frac{980947}{160994728}a^{12}+\frac{6949229}{80497364}a^{11}-\frac{2092565}{40248682}a^{10}-\frac{5165527}{40248682}a^{9}+\frac{5410899}{40248682}a^{8}+\frac{17943125}{40248682}a^{7}-\frac{3515812}{20124341}a^{6}-\frac{5081949}{20124341}a^{5}-\frac{1584365}{40248682}a^{4}+\frac{3150203}{20124341}a^{3}-\frac{13217412}{20124341}a^{2}-\frac{22074408}{20124341}a+\frac{3105588}{20124341}$, $\frac{2522083}{321989456}a^{19}-\frac{415253}{321989456}a^{18}-\frac{8960671}{321989456}a^{17}+\frac{3026577}{321989456}a^{16}+\frac{2517615}{20124341}a^{15}-\frac{6199179}{160994728}a^{14}-\frac{9514245}{40248682}a^{13}+\frac{17570083}{160994728}a^{12}+\frac{41875235}{80497364}a^{11}-\frac{15636281}{80497364}a^{10}-\frac{15839720}{20124341}a^{9}+\frac{23755941}{80497364}a^{8}+\frac{38607241}{20124341}a^{7}-\frac{10050923}{20124341}a^{6}-\frac{46852427}{40248682}a^{5}+\frac{32459287}{40248682}a^{4}+\frac{43486621}{20124341}a^{3}-\frac{11985652}{20124341}a^{2}-\frac{45972067}{20124341}a-\frac{6987605}{20124341}$, $\frac{1019237}{321989456}a^{19}-\frac{2715341}{321989456}a^{18}-\frac{539573}{40248682}a^{17}+\frac{11199403}{321989456}a^{16}+\frac{631802}{20124341}a^{15}-\frac{26983531}{160994728}a^{14}-\frac{728791}{40248682}a^{13}+\frac{58187183}{160994728}a^{12}-\frac{17478205}{80497364}a^{11}-\frac{32729579}{40248682}a^{10}+\frac{49108729}{80497364}a^{9}+\frac{78688645}{80497364}a^{8}-\frac{22494036}{20124341}a^{7}-\frac{33736967}{20124341}a^{6}+\frac{75647847}{40248682}a^{5}+\frac{9932411}{40248682}a^{4}-\frac{72678271}{20124341}a^{3}-\frac{15300126}{20124341}a^{2}+\frac{14035036}{20124341}a-\frac{12153896}{20124341}$ Copy content Toggle raw display (assuming GRH)
sage: UK.fundamental_units()
 
gp: K.fu
 
magma: [K|fUK(g): g in Generators(UK)];
 
oscar: [K(fUK(a)) for a in gens(UK)]
 
Regulator:  \( 28703.22707298631 \) (assuming GRH)
sage: K.regulator()
 
gp: K.reg
 
magma: Regulator(K);
 
oscar: regulator(K)
 

Class number formula

\[ \begin{aligned}\lim_{s\to 1} (s-1)\zeta_K(s) =\mathstrut & \frac{2^{r_1}\cdot (2\pi)^{r_2}\cdot R\cdot h}{w\cdot\sqrt{|D|}}\cr \approx\mathstrut &\frac{2^{0}\cdot(2\pi)^{10}\cdot 28703.22707298631 \cdot 1}{2\cdot\sqrt{84954018740373771557797888}}\cr\approx \mathstrut & 0.149316379403044 \end{aligned}\] (assuming GRH)

# self-contained SageMath code snippet to compute the analytic class number formula
 
x = polygen(QQ); K.<a> = NumberField(x^20 - 4*x^18 + 18*x^16 - 40*x^14 + 92*x^12 - 160*x^10 + 352*x^8 - 352*x^6 + 528*x^4 - 704*x^2 + 352)
 
DK = K.disc(); r1,r2 = K.signature(); RK = K.regulator(); RR = RK.parent()
 
hK = K.class_number(); wK = K.unit_group().torsion_generator().order();
 
2^r1 * (2*RR(pi))^r2 * RK * hK / (wK * RR(sqrt(abs(DK))))
 
# self-contained Pari/GP code snippet to compute the analytic class number formula
 
K = bnfinit(x^20 - 4*x^18 + 18*x^16 - 40*x^14 + 92*x^12 - 160*x^10 + 352*x^8 - 352*x^6 + 528*x^4 - 704*x^2 + 352, 1);
 
[polcoeff (lfunrootres (lfuncreate (K))[1][1][2], -1), 2^K.r1 * (2*Pi)^K.r2 * K.reg * K.no / (K.tu[1] * sqrt (abs (K.disc)))]
 
/* self-contained Magma code snippet to compute the analytic class number formula */
 
Qx<x> := PolynomialRing(QQ); K<a> := NumberField(x^20 - 4*x^18 + 18*x^16 - 40*x^14 + 92*x^12 - 160*x^10 + 352*x^8 - 352*x^6 + 528*x^4 - 704*x^2 + 352);
 
OK := Integers(K); DK := Discriminant(OK);
 
UK, fUK := UnitGroup(OK); clK, fclK := ClassGroup(OK);
 
r1,r2 := Signature(K); RK := Regulator(K); RR := Parent(RK);
 
hK := #clK; wK := #TorsionSubgroup(UK);
 
2^r1 * (2*Pi(RR))^r2 * RK * hK / (wK * Sqrt(RR!Abs(DK)));
 
# self-contained Oscar code snippet to compute the analytic class number formula
 
Qx, x = PolynomialRing(QQ); K, a = NumberField(x^20 - 4*x^18 + 18*x^16 - 40*x^14 + 92*x^12 - 160*x^10 + 352*x^8 - 352*x^6 + 528*x^4 - 704*x^2 + 352);
 
OK = ring_of_integers(K); DK = discriminant(OK);
 
UK, fUK = unit_group(OK); clK, fclK = class_group(OK);
 
r1,r2 = signature(K); RK = regulator(K); RR = parent(RK);
 
hK = order(clK); wK = torsion_units_order(K);
 
2^r1 * (2*pi)^r2 * RK * hK / (wK * sqrt(RR(abs(DK))))
 

Galois group

$C_{10}\wr C_2$ (as 20T53):

sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
magma: G = GaloisGroup(K);
 
oscar: G, Gtx = galois_group(K); G, transitive_group_identification(G)
 
A solvable group of order 200
The 65 conjugacy class representatives for $C_{10}\wr C_2$
Character table for $C_{10}\wr C_2$

Intermediate fields

\(\Q(\sqrt{-2}) \), 4.0.22528.2, 10.0.479756288.1

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

sage: K.subfields()[1:-1]
 
gp: L = nfsubfields(K); L[2..length(b)]
 
magma: L := Subfields(K); L[2..#L];
 
oscar: subfields(K)[2:end-1]
 

Sibling fields

Degree 20 siblings: data not computed
Degree 40 siblings: data not computed
Minimal sibling: This field is its own minimal sibling

Frobenius cycle types

$p$ $2$ $3$ $5$ $7$ $11$ $13$ $17$ $19$ $23$ $29$ $31$ $37$ $41$ $43$ $47$ $53$ $59$
Cycle type R ${\href{/padicField/3.5.0.1}{5} }^{4}$ $20$ ${\href{/padicField/7.10.0.1}{10} }^{2}$ R ${\href{/padicField/13.10.0.1}{10} }^{2}$ ${\href{/padicField/17.10.0.1}{10} }{,}\,{\href{/padicField/17.5.0.1}{5} }^{2}$ ${\href{/padicField/19.5.0.1}{5} }^{2}{,}\,{\href{/padicField/19.2.0.1}{2} }^{5}$ ${\href{/padicField/23.4.0.1}{4} }^{5}$ ${\href{/padicField/29.10.0.1}{10} }^{2}$ $20$ $20$ ${\href{/padicField/41.10.0.1}{10} }{,}\,{\href{/padicField/41.5.0.1}{5} }^{2}$ ${\href{/padicField/43.10.0.1}{10} }{,}\,{\href{/padicField/43.5.0.1}{5} }^{2}$ $20$ $20$ ${\href{/padicField/59.10.0.1}{10} }{,}\,{\href{/padicField/59.2.0.1}{2} }^{5}$

In the table, R denotes a ramified prime. Cycle lengths which are repeated in a cycle type are indicated by exponents.

# to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$ for $p=7$ in Sage:
 
p = 7; [(e, pr.norm().valuation(p)) for pr,e in K.factor(p)]
 
\\ to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$ for $p=7$ in Pari:
 
p = 7; pfac = idealprimedec(K, p); vector(length(pfac), j, [pfac[j][3], pfac[j][4]])
 
// to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$ for $p=7 in Magma:
 
p := 7; [<pr[2], Valuation(Norm(pr[1]), p)> : pr in Factorization(p*Integers(K))];
 
# to obtain a list of $[e_i,f_i]$ for the factorization of the ideal $p\mathcal{O}_K$ for $p=7$ in Oscar:
 
p = 7; pfac = factor(ideal(ring_of_integers(K), p)); [(e, valuation(norm(pr),p)) for (pr,e) in pfac]
 

Local algebras for ramified primes

$p$LabelPolynomial $e$ $f$ $c$ Galois group Slope content
\(2\) Copy content Toggle raw display Deg $20$$4$$5$$55$
\(11\) Copy content Toggle raw display 11.10.9.4$x^{10} + 22$$10$$1$$9$$C_{10}$$[\ ]_{10}$
11.10.0.1$x^{10} + 7 x^{5} + 8 x^{4} + 10 x^{3} + 6 x^{2} + 6 x + 2$$1$$10$$0$$C_{10}$$[\ ]^{10}$