Properties

Label 20.0.493...664.1
Degree $20$
Signature $[0, 10]$
Discriminant $4.934\times 10^{25}$
Root discriminant \(19.26\)
Ramified primes $2,11$
Class number $1$
Class group trivial
Galois group $C_2^4:C_5$ (as 20T17)

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Show commands: Magma / Oscar / PariGP / SageMath

Normalized defining polynomial

sage: x = polygen(QQ); K.<a> = NumberField(x^20 - 8*x^19 + 34*x^18 - 116*x^17 + 338*x^16 - 836*x^15 + 1840*x^14 - 3640*x^13 + 6408*x^12 - 10176*x^11 + 14560*x^10 - 18560*x^9 + 21128*x^8 - 21328*x^7 + 18704*x^6 - 14048*x^5 + 8976*x^4 - 4576*x^3 + 1760*x^2 - 704*x + 352)
 
gp: K = bnfinit(y^20 - 8*y^19 + 34*y^18 - 116*y^17 + 338*y^16 - 836*y^15 + 1840*y^14 - 3640*y^13 + 6408*y^12 - 10176*y^11 + 14560*y^10 - 18560*y^9 + 21128*y^8 - 21328*y^7 + 18704*y^6 - 14048*y^5 + 8976*y^4 - 4576*y^3 + 1760*y^2 - 704*y + 352, 1)
 
magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^20 - 8*x^19 + 34*x^18 - 116*x^17 + 338*x^16 - 836*x^15 + 1840*x^14 - 3640*x^13 + 6408*x^12 - 10176*x^11 + 14560*x^10 - 18560*x^9 + 21128*x^8 - 21328*x^7 + 18704*x^6 - 14048*x^5 + 8976*x^4 - 4576*x^3 + 1760*x^2 - 704*x + 352);
 
oscar: Qx, x = PolynomialRing(QQ); K, a = NumberField(x^20 - 8*x^19 + 34*x^18 - 116*x^17 + 338*x^16 - 836*x^15 + 1840*x^14 - 3640*x^13 + 6408*x^12 - 10176*x^11 + 14560*x^10 - 18560*x^9 + 21128*x^8 - 21328*x^7 + 18704*x^6 - 14048*x^5 + 8976*x^4 - 4576*x^3 + 1760*x^2 - 704*x + 352)
 

\( x^{20} - 8 x^{19} + 34 x^{18} - 116 x^{17} + 338 x^{16} - 836 x^{15} + 1840 x^{14} - 3640 x^{13} + \cdots + 352 \) 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:   \(49338146756019243307761664\) \(\medspace = 2^{30}\cdot 11^{16}\) 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:  \(19.26\)
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:  $2^{15/8}11^{4/5}\approx 24.977294240287762$
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:  \(\Q\)
$\card{ \Aut(K/\Q) }$:  $4$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $\frac{1}{2}a^{4}$, $\frac{1}{2}a^{5}$, $\frac{1}{2}a^{6}$, $\frac{1}{2}a^{7}$, $\frac{1}{4}a^{8}$, $\frac{1}{4}a^{9}$, $\frac{1}{4}a^{10}$, $\frac{1}{4}a^{11}$, $\frac{1}{8}a^{12}$, $\frac{1}{8}a^{13}$, $\frac{1}{8}a^{14}$, $\frac{1}{8}a^{15}$, $\frac{1}{16}a^{16}$, $\frac{1}{16}a^{17}$, $\frac{1}{688}a^{18}+\frac{19}{688}a^{17}+\frac{7}{344}a^{16}-\frac{9}{344}a^{15}-\frac{21}{344}a^{14}-\frac{15}{344}a^{13}+\frac{3}{86}a^{12}+\frac{3}{172}a^{11}-\frac{5}{86}a^{10}+\frac{4}{43}a^{9}-\frac{15}{172}a^{8}-\frac{7}{43}a^{7}+\frac{2}{43}a^{6}+\frac{1}{43}a^{5}+\frac{1}{43}a^{4}-\frac{8}{43}a^{3}-\frac{16}{43}a^{2}+\frac{20}{43}a+\frac{19}{43}$, $\frac{1}{3406356112}a^{19}-\frac{625525}{1703178056}a^{18}+\frac{29140343}{3406356112}a^{17}+\frac{39878045}{1703178056}a^{16}+\frac{5102225}{212897257}a^{15}-\frac{23406541}{1703178056}a^{14}-\frac{1161701}{1703178056}a^{13}+\frac{5472279}{851589028}a^{12}+\frac{36719243}{851589028}a^{11}-\frac{73021841}{851589028}a^{10}-\frac{15395449}{425794514}a^{9}-\frac{30789639}{425794514}a^{8}+\frac{6041046}{212897257}a^{7}-\frac{46713705}{212897257}a^{6}+\frac{64208451}{425794514}a^{5}-\frac{2045967}{425794514}a^{4}-\frac{9305043}{212897257}a^{3}-\frac{14462082}{212897257}a^{2}+\frac{14495725}{212897257}a-\frac{53617858}{212897257}$ 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 $1$

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:   $\frac{23282539}{1703178056}a^{19}-\frac{171319277}{1703178056}a^{18}+\frac{629459989}{1703178056}a^{17}-\frac{3737834429}{3406356112}a^{16}+\frac{2466299073}{851589028}a^{15}-\frac{10847043587}{1703178056}a^{14}+\frac{5230829125}{425794514}a^{13}-\frac{36523783249}{1703178056}a^{12}+\frac{6870119456}{212897257}a^{11}-\frac{35946043133}{851589028}a^{10}+\frac{20855645093}{425794514}a^{9}-\frac{10116219730}{212897257}a^{8}+\frac{182356224}{4951099}a^{7}-\frac{4877567924}{212897257}a^{6}+\frac{1917745790}{212897257}a^{5}+\frac{489441230}{212897257}a^{4}-\frac{768417213}{212897257}a^{3}-\frac{17648850}{212897257}a^{2}-\frac{178612744}{212897257}a+\frac{288028651}{212897257}$, $\frac{6497041}{851589028}a^{19}-\frac{234546375}{3406356112}a^{18}+\frac{255214599}{851589028}a^{17}-\frac{1635908977}{1703178056}a^{16}+\frac{4546236739}{1703178056}a^{15}-\frac{10821070041}{1703178056}a^{14}+\frac{11144274101}{851589028}a^{13}-\frac{20633504155}{851589028}a^{12}+\frac{33828661479}{851589028}a^{11}-\frac{24251773445}{425794514}a^{10}+\frac{15464971843}{212897257}a^{9}-\frac{1604127369}{19804396}a^{8}+\frac{32610490325}{425794514}a^{7}-\frac{13077883057}{212897257}a^{6}+\frac{8599325322}{212897257}a^{5}-\frac{7980556693}{425794514}a^{4}+\frac{925570581}{212897257}a^{3}-\frac{305407903}{212897257}a^{2}+\frac{147250678}{212897257}a+\frac{119563402}{212897257}$, $\frac{29913713}{3406356112}a^{19}-\frac{106678021}{1703178056}a^{18}+\frac{201830345}{851589028}a^{17}-\frac{2533545647}{3406356112}a^{16}+\frac{1709001619}{851589028}a^{15}-\frac{1949861267}{425794514}a^{14}+\frac{1992593433}{212897257}a^{13}-\frac{7257101123}{425794514}a^{12}+\frac{23328024079}{851589028}a^{11}-\frac{33666924197}{851589028}a^{10}+\frac{10739406347}{212897257}a^{9}-\frac{24215580171}{425794514}a^{8}+\frac{11980082269}{212897257}a^{7}-\frac{20149585763}{425794514}a^{6}+\frac{7230889038}{212897257}a^{5}-\frac{8044562637}{425794514}a^{4}+\frac{1647458293}{212897257}a^{3}-\frac{392763470}{212897257}a^{2}+\frac{166921140}{212897257}a-\frac{46242785}{212897257}$, $\frac{575489}{425794514}a^{19}-\frac{36374415}{3406356112}a^{18}+\frac{54886575}{851589028}a^{17}-\frac{964346489}{3406356112}a^{16}+\frac{376861705}{425794514}a^{15}-\frac{2022516287}{851589028}a^{14}+\frac{1213770436}{212897257}a^{13}-\frac{4972931699}{425794514}a^{12}+\frac{4559315626}{212897257}a^{11}-\frac{30169244113}{851589028}a^{10}+\frac{10801920339}{212897257}a^{9}-\frac{54926483883}{851589028}a^{8}+\frac{30874139425}{425794514}a^{7}-\frac{29222663297}{425794514}a^{6}+\frac{11718563063}{212897257}a^{5}-\frac{15636599343}{425794514}a^{4}+\frac{3909234751}{212897257}a^{3}-\frac{961776544}{212897257}a^{2}+\frac{297559578}{212897257}a-\frac{317837733}{212897257}$, $\frac{9593707}{3406356112}a^{19}-\frac{74767985}{3406356112}a^{18}+\frac{38822695}{425794514}a^{17}-\frac{128113399}{425794514}a^{16}+\frac{712058627}{851589028}a^{15}-\frac{420880598}{212897257}a^{14}+\frac{7074024745}{1703178056}a^{13}-\frac{13159673149}{1703178056}a^{12}+\frac{2703061429}{212897257}a^{11}-\frac{3959339839}{212897257}a^{10}+\frac{5075320681}{212897257}a^{9}-\frac{5681599914}{212897257}a^{8}+\frac{5471159706}{212897257}a^{7}-\frac{4302805058}{212897257}a^{6}+\frac{2781933731}{212897257}a^{5}-\frac{2588168401}{425794514}a^{4}+\frac{335272120}{212897257}a^{3}-\frac{201312400}{212897257}a^{2}+\frac{195302092}{212897257}a-\frac{94026704}{212897257}$, $\frac{19927393}{851589028}a^{19}-\frac{599847095}{3406356112}a^{18}+\frac{2272295985}{3406356112}a^{17}-\frac{3443373685}{1703178056}a^{16}+\frac{4585865795}{851589028}a^{15}-\frac{2556734359}{212897257}a^{14}+\frac{40041552387}{1703178056}a^{13}-\frac{17647272521}{425794514}a^{12}+\frac{53858530677}{851589028}a^{11}-\frac{71609756885}{851589028}a^{10}+\frac{20979421138}{212897257}a^{9}-\frac{82357465629}{851589028}a^{8}+\frac{32488491025}{425794514}a^{7}-\frac{20129379345}{425794514}a^{6}+\frac{7355659161}{425794514}a^{5}+\frac{2418008309}{425794514}a^{4}-\frac{2049924407}{212897257}a^{3}+\frac{593243675}{212897257}a^{2}-\frac{167020834}{212897257}a+\frac{10336603}{4951099}$, $\frac{18714275}{3406356112}a^{19}-\frac{46633339}{1703178056}a^{18}+\frac{226638001}{3406356112}a^{17}-\frac{294462437}{1703178056}a^{16}+\frac{81410563}{212897257}a^{15}-\frac{932927155}{1703178056}a^{14}+\frac{156897706}{212897257}a^{13}-\frac{550322321}{851589028}a^{12}-\frac{584683439}{851589028}a^{11}+\frac{590783889}{212897257}a^{10}-\frac{5087593149}{851589028}a^{9}+\frac{9127132871}{851589028}a^{8}-\frac{2935475076}{212897257}a^{7}+\frac{6248841069}{425794514}a^{6}-\frac{3036030053}{212897257}a^{5}+\frac{4792982715}{425794514}a^{4}-\frac{1302848272}{212897257}a^{3}+\frac{877472071}{212897257}a^{2}-\frac{666725324}{212897257}a+\frac{125068743}{212897257}$, $\frac{4903759}{1703178056}a^{19}-\frac{94749357}{3406356112}a^{18}+\frac{109460355}{851589028}a^{17}-\frac{1459904783}{3406356112}a^{16}+\frac{2075041921}{1703178056}a^{15}-\frac{5035682599}{1703178056}a^{14}+\frac{1321472845}{212897257}a^{13}-\frac{9939525459}{851589028}a^{12}+\frac{4130359810}{212897257}a^{11}-\frac{24034421167}{851589028}a^{10}+\frac{15489945699}{425794514}a^{9}-\frac{8686458590}{212897257}a^{8}+\frac{16560575149}{425794514}a^{7}-\frac{6761006227}{212897257}a^{6}+\frac{4664073988}{212897257}a^{5}-\frac{2581794536}{212897257}a^{4}+\frac{1275347623}{212897257}a^{3}-\frac{917017896}{212897257}a^{2}+\frac{504314096}{212897257}a-\frac{50759814}{212897257}$, $\frac{13392837}{3406356112}a^{19}-\frac{36028485}{851589028}a^{18}+\frac{329207279}{1703178056}a^{17}-\frac{1061635689}{1703178056}a^{16}+\frac{382798984}{212897257}a^{15}-\frac{1884282107}{425794514}a^{14}+\frac{1989721990}{212897257}a^{13}-\frac{717236501}{39608792}a^{12}+\frac{13259793067}{425794514}a^{11}-\frac{20129362125}{425794514}a^{10}+\frac{14022340189}{212897257}a^{9}-\frac{34676047523}{425794514}a^{8}+\frac{38027176961}{425794514}a^{7}-\frac{443014109}{4951099}a^{6}+\frac{16660510999}{212897257}a^{5}-\frac{25794871757}{425794514}a^{4}+\frac{8887466958}{212897257}a^{3}-\frac{5299661329}{212897257}a^{2}+\frac{2631469664}{212897257}a-\frac{963837694}{212897257}$ Copy content Toggle raw display
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:  \( 43044.7776734 \)
sage: K.regulator()
 
gp: K.reg
 
magma: Regulator(K);
 
oscar: regulator(K)
 

Class number formula

\[ \begin{aligned}\lim_{s\to 1} (s-1)\zeta_K(s) =\mathstrut & \frac{2^{r_1}\cdot (2\pi)^{r_2}\cdot R\cdot h}{w\cdot\sqrt{|D|}}\cr \approx\mathstrut &\frac{2^{0}\cdot(2\pi)^{10}\cdot 43044.7776734 \cdot 1}{2\cdot\sqrt{49338146756019243307761664}}\cr\approx \mathstrut & 0.293831086298 \end{aligned}\]

# self-contained SageMath code snippet to compute the analytic class number formula
 
x = polygen(QQ); K.<a> = NumberField(x^20 - 8*x^19 + 34*x^18 - 116*x^17 + 338*x^16 - 836*x^15 + 1840*x^14 - 3640*x^13 + 6408*x^12 - 10176*x^11 + 14560*x^10 - 18560*x^9 + 21128*x^8 - 21328*x^7 + 18704*x^6 - 14048*x^5 + 8976*x^4 - 4576*x^3 + 1760*x^2 - 704*x + 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 - 8*x^19 + 34*x^18 - 116*x^17 + 338*x^16 - 836*x^15 + 1840*x^14 - 3640*x^13 + 6408*x^12 - 10176*x^11 + 14560*x^10 - 18560*x^9 + 21128*x^8 - 21328*x^7 + 18704*x^6 - 14048*x^5 + 8976*x^4 - 4576*x^3 + 1760*x^2 - 704*x + 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 - 8*x^19 + 34*x^18 - 116*x^17 + 338*x^16 - 836*x^15 + 1840*x^14 - 3640*x^13 + 6408*x^12 - 10176*x^11 + 14560*x^10 - 18560*x^9 + 21128*x^8 - 21328*x^7 + 18704*x^6 - 14048*x^5 + 8976*x^4 - 4576*x^3 + 1760*x^2 - 704*x + 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 - 8*x^19 + 34*x^18 - 116*x^17 + 338*x^16 - 836*x^15 + 1840*x^14 - 3640*x^13 + 6408*x^12 - 10176*x^11 + 14560*x^10 - 18560*x^9 + 21128*x^8 - 21328*x^7 + 18704*x^6 - 14048*x^5 + 8976*x^4 - 4576*x^3 + 1760*x^2 - 704*x + 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

$C_2^4:C_5$ (as 20T17):

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 80
The 8 conjugacy class representatives for $C_2^4:C_5$
Character table for $C_2^4:C_5$

Intermediate fields

\(\Q(\zeta_{11})^+\), 10.2.219503494144.1 x2, 10.6.219503494144.2

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 10 siblings: data not computed
Degree 16 sibling: data not computed
Degree 20 siblings: data not computed
Degree 40 siblings: data not computed
Minimal sibling: 10.2.219503494144.1

Frobenius cycle types

$p$ $2$ $3$ $5$ $7$ $11$ $13$ $17$ $19$ $23$ $29$ $31$ $37$ $41$ $43$ $47$ $53$ $59$
Cycle type R ${\href{/padicField/3.5.0.1}{5} }^{4}$ ${\href{/padicField/5.5.0.1}{5} }^{4}$ ${\href{/padicField/7.5.0.1}{5} }^{4}$ R ${\href{/padicField/13.5.0.1}{5} }^{4}$ ${\href{/padicField/17.5.0.1}{5} }^{4}$ ${\href{/padicField/19.5.0.1}{5} }^{4}$ ${\href{/padicField/23.2.0.1}{2} }^{8}{,}\,{\href{/padicField/23.1.0.1}{1} }^{4}$ ${\href{/padicField/29.5.0.1}{5} }^{4}$ ${\href{/padicField/31.5.0.1}{5} }^{4}$ ${\href{/padicField/37.5.0.1}{5} }^{4}$ ${\href{/padicField/41.5.0.1}{5} }^{4}$ ${\href{/padicField/43.2.0.1}{2} }^{6}{,}\,{\href{/padicField/43.1.0.1}{1} }^{8}$ ${\href{/padicField/47.5.0.1}{5} }^{4}$ ${\href{/padicField/53.5.0.1}{5} }^{4}$ ${\href{/padicField/59.5.0.1}{5} }^{4}$

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

# 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$$30$
\(11\) Copy content Toggle raw display 11.5.4.4$x^{5} + 11$$5$$1$$4$$C_5$$[\ ]_{5}$
11.5.4.4$x^{5} + 11$$5$$1$$4$$C_5$$[\ ]_{5}$
11.5.4.4$x^{5} + 11$$5$$1$$4$$C_5$$[\ ]_{5}$
11.5.4.4$x^{5} + 11$$5$$1$$4$$C_5$$[\ ]_{5}$