Properties

Label 16.8.484...304.44
Degree $16$
Signature $[8, 4]$
Discriminant $4.841\times 10^{23}$
Root discriminant \(30.22\)
Ramified primes $2,3$
Class number $1$
Class group trivial
Galois group $C_2^2 : C_8$ (as 16T24)

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Normalized defining polynomial

Copy content comment:Define the number field
 
Copy content sage:x = polygen(QQ); K.<a> = NumberField(x^16 - 8*x^14 + 52*x^12 - 408*x^10 + 1822*x^8 - 4024*x^6 + 4500*x^4 - 2472*x^2 + 289)
 
Copy content gp:K = bnfinit(y^16 - 8*y^14 + 52*y^12 - 408*y^10 + 1822*y^8 - 4024*y^6 + 4500*y^4 - 2472*y^2 + 289, 1)
 
Copy content magma:R<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^16 - 8*x^14 + 52*x^12 - 408*x^10 + 1822*x^8 - 4024*x^6 + 4500*x^4 - 2472*x^2 + 289);
 
Copy content oscar:Qx, x = polynomial_ring(QQ); K, a = number_field(x^16 - 8*x^14 + 52*x^12 - 408*x^10 + 1822*x^8 - 4024*x^6 + 4500*x^4 - 2472*x^2 + 289)
 

\( x^{16} - 8x^{14} + 52x^{12} - 408x^{10} + 1822x^{8} - 4024x^{6} + 4500x^{4} - 2472x^{2} + 289 \) Copy content Toggle raw display

Copy content comment:Defining polynomial
 
Copy content sage:K.defining_polynomial()
 
Copy content gp:K.pol
 
Copy content magma:DefiningPolynomial(K);
 
Copy content oscar:defining_polynomial(K)
 

Invariants

Degree:  $16$
Copy content comment:Degree over Q
 
Copy content sage:K.degree()
 
Copy content gp:poldegree(K.pol)
 
Copy content magma:Degree(K);
 
Copy content oscar:degree(K)
 
Signature:  $[8, 4]$
Copy content comment:Signature
 
Copy content sage:K.signature()
 
Copy content gp:K.sign
 
Copy content magma:Signature(K);
 
Copy content oscar:signature(K)
 
Discriminant:   \(484116351470433472610304\) \(\medspace = 2^{66}\cdot 3^{8}\) Copy content Toggle raw display
Copy content comment:Discriminant
 
Copy content sage:K.disc()
 
Copy content gp:K.disc
 
Copy content magma:OK := Integers(K); Discriminant(OK);
 
Copy content oscar:OK = ring_of_integers(K); discriminant(OK)
 
Root discriminant:  \(30.22\)
Copy content comment:Root discriminant
 
Copy content sage:(K.disc().abs())^(1./K.degree())
 
Copy content gp:abs(K.disc)^(1/poldegree(K.pol))
 
Copy content magma:Abs(Discriminant(OK))^(1/Degree(K));
 
Copy content oscar:OK = ring_of_integers(K); (1.0 * abs(discriminant(OK)))^(1/degree(K))
 
Galois root discriminant:  $2^{67/16}3^{1/2}\approx 31.559036391689393$
Ramified primes:   \(2\), \(3\) Copy content Toggle raw display
Copy content comment:Ramified primes
 
Copy content sage:K.disc().support()
 
Copy content gp:factor(abs(K.disc))[,1]~
 
Copy content magma:PrimeDivisors(Discriminant(OK));
 
Copy content oscar:prime_divisors(discriminant(OK))
 
Discriminant root field:  \(\Q\)
$\Aut(K/\Q)$:   $C_2\times C_4$
Copy content comment:Autmorphisms
 
Copy content sage:K.automorphisms()
 
Copy content magma:Automorphisms(K);
 
Copy content oscar:automorphisms(K)
 
This field is not Galois over $\Q$.
This is not a CM field.
This field has no CM subfields.

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

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $\frac{1}{2}a^{6}-\frac{1}{2}a^{4}-\frac{1}{2}a^{2}-\frac{1}{2}$, $\frac{1}{2}a^{7}-\frac{1}{2}a^{5}-\frac{1}{2}a^{3}-\frac{1}{2}a$, $\frac{1}{2}a^{8}-\frac{1}{2}$, $\frac{1}{34}a^{9}+\frac{4}{17}a^{7}+\frac{5}{17}a^{5}+\frac{2}{17}a^{3}+\frac{9}{34}a$, $\frac{1}{34}a^{10}+\frac{4}{17}a^{8}-\frac{7}{34}a^{6}-\frac{13}{34}a^{4}-\frac{4}{17}a^{2}-\frac{1}{2}$, $\frac{1}{68}a^{11}-\frac{1}{68}a^{10}-\frac{1}{68}a^{9}+\frac{9}{68}a^{8}+\frac{3}{34}a^{7}-\frac{5}{34}a^{6}-\frac{9}{34}a^{5}+\frac{15}{34}a^{4}-\frac{27}{68}a^{3}-\frac{9}{68}a^{2}-\frac{13}{68}a+\frac{1}{4}$, $\frac{1}{68}a^{12}-\frac{3}{68}a^{8}-\frac{2}{17}a^{6}+\frac{11}{68}a^{4}-\frac{1}{17}a^{2}-\frac{1}{4}$, $\frac{1}{68}a^{13}-\frac{1}{68}a^{9}+\frac{2}{17}a^{7}+\frac{31}{68}a^{5}+\frac{1}{17}a^{3}+\frac{1}{68}a$, $\frac{1}{519044}a^{14}+\frac{1561}{519044}a^{12}+\frac{6701}{519044}a^{10}+\frac{71517}{519044}a^{8}-\frac{69435}{519044}a^{6}-\frac{223087}{519044}a^{4}+\frac{213569}{519044}a^{2}+\frac{629}{1796}$, $\frac{1}{519044}a^{15}+\frac{1561}{519044}a^{13}-\frac{233}{129761}a^{11}-\frac{1}{68}a^{10}+\frac{705}{129761}a^{9}+\frac{9}{68}a^{8}+\frac{52693}{519044}a^{7}-\frac{5}{34}a^{6}-\frac{70427}{519044}a^{5}+\frac{15}{34}a^{4}-\frac{72591}{259522}a^{3}-\frac{9}{68}a^{2}-\frac{4307}{15266}a+\frac{1}{4}$ Copy content Toggle raw display

Copy content comment:Integral basis
 
Copy content sage:K.integral_basis()
 
Copy content gp:K.zk
 
Copy content magma:IntegralBasis(K);
 
Copy content oscar:basis(OK)
 

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

Class group and class number

Ideal class group:  Trivial group, which has order $1$
Copy content comment:Class group
 
Copy content sage:K.class_group().invariants()
 
Copy content gp:K.clgp
 
Copy content magma:ClassGroup(K);
 
Copy content oscar:class_group(K)
 
Narrow class group:  $C_{2}$, which has order $2$
Copy content comment:Narrow class group
 
Copy content sage:K.narrow_class_group().invariants()
 
Copy content gp:bnfnarrow(K)
 
Copy content magma:NarrowClassGroup(K);
 

Unit group

Copy content comment:Unit group
 
Copy content sage:UK = K.unit_group()
 
Copy content magma:UK, fUK := UnitGroup(K);
 
Copy content oscar:UK, fUK = unit_group(OK)
 
Rank:  $11$
Copy content comment:Unit rank
 
Copy content sage:UK.rank()
 
Copy content gp:K.fu
 
Copy content magma:UnitRank(K);
 
Copy content oscar:rank(UK)
 
Torsion generator:   \( -1 \)  (order $2$) Copy content Toggle raw display
Copy content comment:Generator for roots of unity
 
Copy content sage:UK.torsion_generator()
 
Copy content gp:K.tu[2]
 
Copy content magma:K!f(TU.1) where TU,f is TorsionUnitGroup(K);
 
Copy content oscar:torsion_units_generator(OK)
 
Fundamental units:   $\frac{105}{129761}a^{14}+\frac{409}{259522}a^{12}-\frac{1369}{129761}a^{10}+\frac{16853}{129761}a^{8}+\frac{24059}{129761}a^{6}-\frac{758751}{259522}a^{4}+\frac{626915}{129761}a^{2}-\frac{491}{449}$, $\frac{5781}{519044}a^{14}+\frac{5241}{129761}a^{12}-\frac{191831}{519044}a^{10}+\frac{725969}{259522}a^{8}-\frac{3587979}{519044}a^{6}+\frac{771408}{129761}a^{4}-\frac{264161}{519044}a^{2}-\frac{797}{898}$, $\frac{5017}{519044}a^{15}+\frac{30453}{519044}a^{13}-\frac{216909}{519044}a^{11}+\frac{1690535}{519044}a^{9}-\frac{6395913}{519044}a^{7}+\frac{11847105}{519044}a^{5}-\frac{10977185}{519044}a^{3}+\frac{236811}{30532}a-1$, $\frac{756}{129761}a^{15}+\frac{2999}{129761}a^{13}-\frac{48719}{259522}a^{11}+\frac{196145}{129761}a^{9}-\frac{967953}{259522}a^{7}+\frac{516685}{259522}a^{5}+\frac{162978}{129761}a^{3}-\frac{18633}{15266}a+1$, $\frac{2073}{519044}a^{14}+\frac{2018}{129761}a^{12}-\frac{75443}{519044}a^{10}+\frac{275297}{259522}a^{8}-\frac{1561491}{519044}a^{6}+\frac{610335}{129761}a^{4}-\frac{2029649}{519044}a^{2}-\frac{1133}{898}$, $\frac{3715}{519044}a^{15}-\frac{2073}{519044}a^{14}+\frac{17231}{519044}a^{13}+\frac{2018}{129761}a^{12}-\frac{132763}{519044}a^{11}-\frac{75443}{519044}a^{10}+\frac{1057163}{519044}a^{9}+\frac{275297}{259522}a^{8}-\frac{3143373}{519044}a^{7}-\frac{1561491}{519044}a^{6}+\frac{3701969}{519044}a^{5}+\frac{610335}{129761}a^{4}-\frac{2614769}{519044}a^{3}-\frac{2029649}{519044}a^{2}+\frac{117969}{30532}a-\frac{1133}{898}$, $\frac{811}{519044}a^{15}+\frac{2073}{519044}a^{14}+\frac{1107}{519044}a^{13}-\frac{2018}{129761}a^{12}-\frac{15081}{519044}a^{11}+\frac{75443}{519044}a^{10}+\frac{132641}{519044}a^{9}-\frac{275297}{259522}a^{8}+\frac{117639}{519044}a^{7}+\frac{1561491}{519044}a^{6}-\frac{1749399}{519044}a^{5}-\frac{610335}{129761}a^{4}+\frac{2690393}{519044}a^{3}+\frac{2029649}{519044}a^{2}-\frac{88041}{30532}a-\frac{663}{898}$, $\frac{1457}{129761}a^{15}-\frac{7890}{129761}a^{13}+\frac{115995}{259522}a^{11}-\frac{455794}{129761}a^{9}+\frac{3139137}{259522}a^{7}-\frac{5048853}{259522}a^{5}+\frac{2071698}{129761}a^{3}-\frac{89651}{15266}a$, $\frac{2715}{259522}a^{15}-\frac{6733}{129761}a^{13}+\frac{103005}{259522}a^{11}-\frac{400532}{129761}a^{9}+\frac{1295698}{129761}a^{7}-\frac{3635963}{259522}a^{5}+\frac{1022317}{129761}a^{3}-\frac{17907}{15266}a$, $\frac{1771}{259522}a^{15}-\frac{166}{129761}a^{14}+\frac{35395}{519044}a^{13}-\frac{6049}{519044}a^{12}-\frac{52509}{129761}a^{11}+\frac{2052}{129761}a^{10}+\frac{1682417}{519044}a^{9}-\frac{124523}{519044}a^{8}-\frac{4120065}{259522}a^{7}+\frac{863289}{259522}a^{6}+\frac{18745009}{519044}a^{5}-\frac{5148505}{519044}a^{4}-\frac{5057004}{129761}a^{3}+\frac{3280219}{259522}a^{2}+\frac{578203}{30532}a-\frac{13107}{1796}$, $\frac{2253}{519044}a^{15}+\frac{7071}{259522}a^{14}-\frac{8573}{259522}a^{13}-\frac{67671}{519044}a^{12}+\frac{106141}{519044}a^{11}+\frac{132131}{129761}a^{10}-\frac{433679}{259522}a^{9}-\frac{4108539}{519044}a^{8}+\frac{3626955}{519044}a^{7}+\frac{6452459}{259522}a^{6}-\frac{3368583}{259522}a^{5}-\frac{18061573}{519044}a^{4}+\frac{5680855}{519044}a^{3}+\frac{2928829}{129761}a^{2}-\frac{60049}{15266}a-\frac{3413}{1796}$ Copy content Toggle raw display
Copy content comment:Fundamental units
 
Copy content sage:UK.fundamental_units()
 
Copy content gp:K.fu
 
Copy content magma:[K|fUK(g): g in Generators(UK)];
 
Copy content oscar:[K(fUK(a)) for a in gens(UK)]
 
Regulator:  \( 1063863.751199081 \)
Copy content comment:Regulator
 
Copy content sage:K.regulator()
 
Copy content gp:K.reg
 
Copy content magma:Regulator(K);
 
Copy content oscar:regulator(K)
 

Class number formula

\[ \begin{aligned}\lim_{s\to 1} (s-1)\zeta_K(s) =\mathstrut & \frac{2^{r_1}\cdot (2\pi)^{r_2}\cdot R\cdot h}{w\cdot\sqrt{|D|}}\cr \approx\mathstrut &\frac{2^{8}\cdot(2\pi)^{4}\cdot 1063863.751199081 \cdot 1}{2\cdot\sqrt{484116351470433472610304}}\cr\approx \mathstrut & 0.305028612196671 \end{aligned}\]

Copy content comment:Analytic class number formula
 
Copy content sage:# self-contained SageMath code snippet to compute the analytic class number formula x = polygen(QQ); K.<a> = NumberField(x^16 - 8*x^14 + 52*x^12 - 408*x^10 + 1822*x^8 - 4024*x^6 + 4500*x^4 - 2472*x^2 + 289) 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))))
 
Copy content gp:\\ self-contained Pari/GP code snippet to compute the analytic class number formula K = bnfinit(x^16 - 8*x^14 + 52*x^12 - 408*x^10 + 1822*x^8 - 4024*x^6 + 4500*x^4 - 2472*x^2 + 289, 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)))]
 
Copy content magma:/* self-contained Magma code snippet to compute the analytic class number formula */ Qx<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^16 - 8*x^14 + 52*x^12 - 408*x^10 + 1822*x^8 - 4024*x^6 + 4500*x^4 - 2472*x^2 + 289); 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)));
 
Copy content oscar:# self-contained Oscar code snippet to compute the analytic class number formula Qx, x = polynomial_ring(QQ); K, a = number_field(x^16 - 8*x^14 + 52*x^12 - 408*x^10 + 1822*x^8 - 4024*x^6 + 4500*x^4 - 2472*x^2 + 289); 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

$C_2^2:C_8$ (as 16T24):

Copy content comment:Galois group
 
Copy content sage:K.galois_group(type='pari')
 
Copy content gp:polgalois(K.pol)
 
Copy content magma:G = GaloisGroup(K);
 
Copy content oscar:G, Gtx = galois_group(K); degree(K) > 1 ? (G, transitive_group_identification(G)) : (G, nothing)
 
A solvable group of order 32
The 20 conjugacy class representatives for $C_2^2 : C_8$
Character table for $C_2^2 : C_8$

Intermediate fields

\(\Q(\sqrt{2}) \), 4.2.9216.1, \(\Q(\zeta_{16})^+\), 4.2.18432.3, 8.4.173946175488.1, \(\Q(\zeta_{32})^+\), 8.4.5435817984.1

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

Copy content comment:Intermediate fields
 
Copy content sage:K.subfields()[1:-1]
 
Copy content gp:L = nfsubfields(K); L[2..length(L)]
 
Copy content magma:L := Subfields(K); L[2..#L];
 
Copy content oscar:subfields(K)[2:end-1]
 

Sibling fields

Galois closure: deg 32
Degree 16 sibling: 16.0.484116351470433472610304.196
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 R ${\href{/padicField/5.8.0.1}{8} }^{2}$ ${\href{/padicField/7.4.0.1}{4} }^{4}$ ${\href{/padicField/11.8.0.1}{8} }^{2}$ ${\href{/padicField/13.8.0.1}{8} }^{2}$ ${\href{/padicField/17.2.0.1}{2} }^{8}$ ${\href{/padicField/19.8.0.1}{8} }^{2}$ ${\href{/padicField/23.4.0.1}{4} }^{4}$ ${\href{/padicField/29.8.0.1}{8} }^{2}$ ${\href{/padicField/31.2.0.1}{2} }^{4}{,}\,{\href{/padicField/31.1.0.1}{1} }^{8}$ ${\href{/padicField/37.8.0.1}{8} }^{2}$ ${\href{/padicField/41.4.0.1}{4} }^{4}$ ${\href{/padicField/43.8.0.1}{8} }^{2}$ ${\href{/padicField/47.2.0.1}{2} }^{8}$ ${\href{/padicField/53.8.0.1}{8} }^{2}$ ${\href{/padicField/59.8.0.1}{8} }^{2}$

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

Copy content comment:Frobenius cycle types
 
Copy content sage:# to obtain a list of [e_i,f_i] for the factorization of the ideal pO_K for p=7 in Sage: p = 7; [(e, pr.norm().valuation(p)) for pr,e in K.factor(p)]
 
Copy content gp:\\ to obtain a list of [e_i,f_i] for the factorization of the ideal pO_K for p=7 in Pari: p = 7; pfac = idealprimedec(K, p); vector(length(pfac), j, [pfac[j][3], pfac[j][4]])
 
Copy content magma:// to obtain a list of [e_i,f_i] for the factorization of the ideal pO_K for p=7 in Magma: p := 7; [<pr[2], Valuation(Norm(pr[1]), p)> : pr in Factorization(p*Integers(K))];
 
Copy content oscar:# to obtain a list of [e_i,f_i] for the factorization of the ideal pO_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 2.1.16.66h1.519$x^{16} + 16 x^{13} + 4 x^{12} + 8 x^{10} + 8 x^{8} + 16 x^{7} + 8 x^{6} + 16 x^{5} + 16 x^{3} + 2$$16$$1$$66$$C_2^2 : C_8$$$[2, 3, \frac{7}{2}, 4, 5]$$
\(3\) Copy content Toggle raw display 3.8.2.8a1.2$x^{16} + 4 x^{13} + 2 x^{12} + 8 x^{10} + 8 x^{9} + 5 x^{8} + 8 x^{7} + 12 x^{6} + 12 x^{5} + 8 x^{4} + 8 x^{3} + 12 x^{2} + 8 x + 7$$2$$8$$8$$C_8\times C_2$$$[\ ]_{2}^{8}$$

Spectrum of ring of integers

(0)(0)(2)(3)(5)(7)(11)(13)(17)(19)(23)(29)(31)(37)(41)(43)(47)(53)(59)