Properties

Label 16.16.817...873.1
Degree $16$
Signature $[16, 0]$
Discriminant $8.175\times 10^{22}$
Root discriminant $27.04$
Ramified primes $13, 17$
Class number $1$ (GRH)
Class group trivial (GRH)
Galois group $C_{16} : C_2$ (as 16T22)

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Normalized defining polynomial

sage: x = polygen(QQ); K.<a> = NumberField(x^16 - 3*x^15 - 25*x^14 + 92*x^13 + 98*x^12 - 583*x^11 + 49*x^10 + 1383*x^9 - 647*x^8 - 1357*x^7 + 807*x^6 + 520*x^5 - 251*x^4 - 114*x^3 + 19*x^2 + 11*x + 1)
 
gp: K = bnfinit(x^16 - 3*x^15 - 25*x^14 + 92*x^13 + 98*x^12 - 583*x^11 + 49*x^10 + 1383*x^9 - 647*x^8 - 1357*x^7 + 807*x^6 + 520*x^5 - 251*x^4 - 114*x^3 + 19*x^2 + 11*x + 1, 1)
 
magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![1, 11, 19, -114, -251, 520, 807, -1357, -647, 1383, 49, -583, 98, 92, -25, -3, 1]);
 

\( x^{16} - 3 x^{15} - 25 x^{14} + 92 x^{13} + 98 x^{12} - 583 x^{11} + 49 x^{10} + 1383 x^{9} - 647 x^{8} - 1357 x^{7} + 807 x^{6} + 520 x^{5} - 251 x^{4} - 114 x^{3} + 19 x^{2} + 11 x + 1 \)

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

Invariants

Degree:  $16$
sage: K.degree()
 
gp: poldegree(K.pol)
 
magma: Degree(K);
 
Signature:  $[16, 0]$
sage: K.signature()
 
gp: K.sign
 
magma: Signature(K);
 
Discriminant:  \(81753664774171848863873\)\(\medspace = 13^{4}\cdot 17^{15}\)
sage: K.disc()
 
gp: K.disc
 
magma: Discriminant(Integers(K));
 
Root discriminant:  $27.04$
sage: (K.disc().abs())^(1./K.degree())
 
gp: abs(K.disc)^(1/poldegree(K.pol))
 
magma: Abs(Discriminant(Integers(K)))^(1/Degree(K));
 
Ramified primes:  $13, 17$
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
magma: PrimeDivisors(Discriminant(Integers(K)));
 
$|\Aut(K/\Q)|$:  $8$
This field is not Galois over $\Q$.
This is not a CM field.

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

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $\frac{1}{103} a^{14} - \frac{25}{103} a^{13} + \frac{9}{103} a^{12} + \frac{22}{103} a^{11} + \frac{17}{103} a^{10} + \frac{51}{103} a^{9} + \frac{43}{103} a^{8} - \frac{26}{103} a^{7} - \frac{15}{103} a^{6} + \frac{29}{103} a^{5} - \frac{22}{103} a^{4} + \frac{48}{103} a^{3} - \frac{49}{103} a^{2} - \frac{11}{103} a + \frac{1}{103}$, $\frac{1}{2549095397} a^{15} - \frac{7272992}{2549095397} a^{14} + \frac{1027924379}{2549095397} a^{13} + \frac{1194144945}{2549095397} a^{12} + \frac{78928993}{2549095397} a^{11} + \frac{1239857956}{2549095397} a^{10} + \frac{396383097}{2549095397} a^{9} + \frac{155290479}{2549095397} a^{8} + \frac{341311969}{2549095397} a^{7} + \frac{1017202377}{2549095397} a^{6} - \frac{769072344}{2549095397} a^{5} + \frac{1223619063}{2549095397} a^{4} + \frac{973861671}{2549095397} a^{3} - \frac{1270128219}{2549095397} a^{2} + \frac{1007307724}{2549095397} a + \frac{534884425}{2549095397}$

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

Class group and class number

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

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

Unit group

sage: UK = K.unit_group()
 
magma: UK, f := UnitGroup(K);
 
Rank:  $15$
sage: UK.rank()
 
gp: K.fu
 
magma: UnitRank(K);
 
Torsion generator:  \( -1 \) (order $2$)
sage: UK.torsion_generator()
 
gp: K.tu[2]
 
magma: K!f(TU.1) where TU,f is TorsionUnitGroup(K);
 
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)
sage: UK.fundamental_units()
 
gp: K.fu
 
magma: [K!f(g): g in Generators(UK)];
 
Regulator:  \( 1330090.29679 \) (assuming GRH)
sage: K.regulator()
 
gp: K.reg
 
magma: Regulator(K);
 

Class number formula

$\displaystyle\lim_{s\to 1} (s-1)\zeta_K(s) \approx\frac{2^{16}\cdot(2\pi)^{0}\cdot 1330090.29679 \cdot 1}{2\sqrt{81753664774171848863873}}\approx 0.152432455359$ (assuming GRH)

Galois group

$OD_{32}$ (as 16T22):

sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
magma: GaloisGroup(K);
 
A solvable group of order 32
The 20 conjugacy class representatives for $C_{16} : C_2$
Character table for $C_{16} : C_2$

Intermediate fields

\(\Q(\sqrt{17}) \), 4.4.4913.1, \(\Q(\zeta_{17})^+\)

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

Sibling fields

Galois closure: Deg 32

Frobenius cycle types

$p$ $2$ $3$ $5$ $7$ $11$ $13$ $17$ $19$ $23$ $29$ $31$ $37$ $41$ $43$ $47$ $53$ $59$
Cycle type ${\href{/LocalNumberField/2.8.0.1}{8} }^{2}$ $16$ $16$ $16$ $16$ R R ${\href{/LocalNumberField/19.8.0.1}{8} }^{2}$ $16$ $16$ $16$ $16$ $16$ ${\href{/LocalNumberField/43.8.0.1}{8} }^{2}$ ${\href{/LocalNumberField/47.4.0.1}{4} }^{4}$ ${\href{/LocalNumberField/53.8.0.1}{8} }^{2}$ ${\href{/LocalNumberField/59.8.0.1}{8} }^{2}$

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

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]])
 
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];
 

Local algebras for ramified primes

$p$LabelPolynomial $e$ $f$ $c$ Galois group Slope content
$13$13.4.0.1$x^{4} + x^{2} - x + 2$$1$$4$$0$$C_4$$[\ ]^{4}$
13.4.2.2$x^{4} - 13 x^{2} + 338$$2$$2$$2$$C_4$$[\ ]_{2}^{2}$
13.4.2.2$x^{4} - 13 x^{2} + 338$$2$$2$$2$$C_4$$[\ ]_{2}^{2}$
13.4.0.1$x^{4} + x^{2} - x + 2$$1$$4$$0$$C_4$$[\ ]^{4}$
17Data not computed