magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![34, -16, -28, 22, -1, -4, 2, -2, 1]);
sage: x = polygen(QQ); K.<a> = NumberField(x^8 - 2*x^7 + 2*x^6 - 4*x^5 - x^4 + 22*x^3 - 28*x^2 - 16*x + 34)
gp: K = bnfinit(x^8 - 2*x^7 + 2*x^6 - 4*x^5 - x^4 + 22*x^3 - 28*x^2 - 16*x + 34, 1)
Normalized defining polynomial
\( x^{8} - 2 x^{7} + 2 x^{6} - 4 x^{5} - x^{4} + 22 x^{3} - 28 x^{2} - 16 x + 34 \)
magma: DefiningPolynomial(K);
sage: K.defining_polynomial()
gp: K.pol
Invariants
| Degree: | $8$ | magma: Degree(K);
sage: K.degree()
gp: poldegree(K.pol)
| |
| Signature: | $[0, 4]$ | magma: Signature(K);
sage: K.signature()
gp: K.sign
| |
| Discriminant: | \(45174951936=2^{12}\cdot 3^{8}\cdot 41^{2}\) | magma: Discriminant(Integers(K));
sage: K.disc()
gp: K.disc
| |
| Root discriminant: | $21.47$ | 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: | $2, 3, 41$ | magma: PrimeDivisors(Discriminant(Integers(K)));
sage: K.disc().support()
gp: factor(abs(K.disc))[,1]~
| |
| This field is not Galois over $\Q$. | |||
| This is not a CM field. | |||
Integral basis (with respect to field generator \(a\))
$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $\frac{1}{2} a^{6} - \frac{1}{2} a^{4}$, $\frac{1}{4} a^{7} - \frac{1}{4} a^{6} + \frac{1}{4} a^{5} + \frac{1}{4} a^{4} - \frac{1}{2} a^{2} - \frac{1}{2} a - \frac{1}{2}$
magma: IntegralBasis(K);
sage: K.integral_basis()
gp: K.zk
Class group and class number
$C_{2}$, which has order $2$
magma: ClassGroup(K);
sage: K.class_group().invariants()
gp: K.clgp
Unit group
magma: UK, f := UnitGroup(K);
sage: UK = K.unit_group()
| Rank: | $3$ | magma: UnitRank(K);
sage: UK.rank()
gp: K.fu
| |
| Torsion generator: | \( a^{7} - \frac{3}{2} a^{6} + 3 a^{5} - \frac{11}{2} a^{4} + 2 a^{3} + 12 a^{2} - 16 a - 4 \) (order $4$) | magma: K!f(TU.1) where TU,f is TorsionUnitGroup(K);
sage: UK.torsion_generator()
gp: K.tu[2]
| |
| Fundamental units: | \( \frac{1}{4} a^{7} - \frac{1}{4} a^{6} + \frac{1}{4} a^{5} - \frac{3}{4} a^{4} - a^{3} + \frac{9}{2} a^{2} - \frac{5}{2} a - \frac{15}{2} \), \( \frac{23}{4} a^{7} - \frac{13}{4} a^{6} + \frac{35}{4} a^{5} - \frac{55}{4} a^{4} - 19 a^{3} + \frac{175}{2} a^{2} - \frac{59}{2} a - \frac{223}{2} \), \( \frac{39}{4} a^{7} - \frac{169}{4} a^{6} + \frac{307}{4} a^{5} - \frac{587}{4} a^{4} + 193 a^{3} + \frac{45}{2} a^{2} - \frac{941}{2} a + \frac{941}{2} \) | magma: [K!f(g): g in Generators(UK)];
sage: UK.fundamental_units()
gp: K.fu
| |
| Regulator: | \( 471.799300951 \) | magma: Regulator(K);
sage: K.regulator()
gp: K.reg
|
Galois group
$C_2^2:S_4$ (as 8T34):
magma: GaloisGroup(K);
sage: K.galois_group(type='pari')
gp: polgalois(K.pol)
| A solvable group of order 96 |
| The 10 conjugacy class representatives for $V_4^2:S_3$ |
| Character table for $V_4^2:S_3$ |
Intermediate fields
| \(\Q(\sqrt{-1}) \) |
Fields in the database are given up to isomorphism. Isomorphic intermediate fields are shown with their multiplicities.
Sibling fields
| Degree 12 siblings: | data not computed |
| Degree 16 sibling: | data not computed |
| Degree 24 siblings: | data not computed |
| Degree 32 sibling: | data not computed |
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 | ${\href{/LocalNumberField/5.3.0.1}{3} }^{2}{,}\,{\href{/LocalNumberField/5.1.0.1}{1} }^{2}$ | ${\href{/LocalNumberField/7.4.0.1}{4} }^{2}$ | ${\href{/LocalNumberField/11.2.0.1}{2} }^{4}$ | ${\href{/LocalNumberField/13.3.0.1}{3} }^{2}{,}\,{\href{/LocalNumberField/13.1.0.1}{1} }^{2}$ | ${\href{/LocalNumberField/17.3.0.1}{3} }^{2}{,}\,{\href{/LocalNumberField/17.1.0.1}{1} }^{2}$ | ${\href{/LocalNumberField/19.4.0.1}{4} }^{2}$ | ${\href{/LocalNumberField/23.4.0.1}{4} }^{2}$ | ${\href{/LocalNumberField/29.3.0.1}{3} }^{2}{,}\,{\href{/LocalNumberField/29.1.0.1}{1} }^{2}$ | ${\href{/LocalNumberField/31.4.0.1}{4} }^{2}$ | ${\href{/LocalNumberField/37.3.0.1}{3} }^{2}{,}\,{\href{/LocalNumberField/37.1.0.1}{1} }^{2}$ | R | ${\href{/LocalNumberField/43.4.0.1}{4} }^{2}$ | ${\href{/LocalNumberField/47.4.0.1}{4} }^{2}$ | ${\href{/LocalNumberField/53.2.0.1}{2} }^{2}{,}\,{\href{/LocalNumberField/53.1.0.1}{1} }^{4}$ | ${\href{/LocalNumberField/59.2.0.1}{2} }^{4}$ |
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
| $p$ | Label | Polynomial | $e$ | $f$ | $c$ | Galois group | Slope content |
|---|---|---|---|---|---|---|---|
| $2$ | 2.4.6.8 | $x^{4} + 2 x^{3} + 2$ | $4$ | $1$ | $6$ | $D_{4}$ | $[2, 2]^{2}$ |
| 2.4.6.8 | $x^{4} + 2 x^{3} + 2$ | $4$ | $1$ | $6$ | $D_{4}$ | $[2, 2]^{2}$ | |
| $3$ | 3.2.0.1 | $x^{2} - x + 2$ | $1$ | $2$ | $0$ | $C_2$ | $[\ ]^{2}$ |
| 3.6.8.5 | $x^{6} + 9 x^{2} + 9$ | $3$ | $2$ | $8$ | $S_3$ | $[2]^{2}$ | |
| $41$ | 41.2.0.1 | $x^{2} - x + 12$ | $1$ | $2$ | $0$ | $C_2$ | $[\ ]^{2}$ |
| 41.2.1.1 | $x^{2} - 41$ | $2$ | $1$ | $1$ | $C_2$ | $[\ ]_{2}$ | |
| 41.2.1.1 | $x^{2} - 41$ | $2$ | $1$ | $1$ | $C_2$ | $[\ ]_{2}$ | |
| 41.2.0.1 | $x^{2} - x + 12$ | $1$ | $2$ | $0$ | $C_2$ | $[\ ]^{2}$ |
Artin representations
| Label | Dimension | Conductor | Defining polynomial of Artin field | $G$ | Ind | $\chi(c)$ | |
|---|---|---|---|---|---|---|---|
| * | 1.1.1t1.1c1 | $1$ | $1$ | $x$ | $C_1$ | $1$ | $1$ |
| * | 1.2e2.2t1.1c1 | $1$ | $ 2^{2}$ | $x^{2} + 1$ | $C_2$ (as 2T1) | $1$ | $-1$ |
| 2.2e2_3e4.3t2.1c1 | $2$ | $ 2^{2} \cdot 3^{4}$ | $x^{3} - 3 x - 4$ | $S_3$ (as 3T2) | $1$ | $0$ | |
| 3.2e4_3e4_41e2.6t8.1c1 | $3$ | $ 2^{4} \cdot 3^{4} \cdot 41^{2}$ | $x^{4} - x^{3} + 18 x^{2} + 27 x - 9$ | $S_4$ (as 4T5) | $1$ | $-1$ | |
| 3.2e4_3e4_41e2.4t5.2c1 | $3$ | $ 2^{4} \cdot 3^{4} \cdot 41^{2}$ | $x^{4} - 2 x^{3} - 6 x^{2} - 34 x + 125$ | $S_4$ (as 4T5) | $1$ | $1$ | |
| 3.2e6_3e4_41e2.6t8.3c1 | $3$ | $ 2^{6} \cdot 3^{4} \cdot 41^{2}$ | $x^{4} - 15 x^{2} - 82 x + 87$ | $S_4$ (as 4T5) | $1$ | $-1$ | |
| 3.2e2_3e4_41e2.4t5.1c1 | $3$ | $ 2^{2} \cdot 3^{4} \cdot 41^{2}$ | $x^{4} - x^{3} + 18 x^{2} + 27 x - 9$ | $S_4$ (as 4T5) | $1$ | $1$ | |
| 3.2e6_3e4_41e2.6t8.4c1 | $3$ | $ 2^{6} \cdot 3^{4} \cdot 41^{2}$ | $x^{4} - 2 x^{3} - 6 x^{2} - 34 x + 125$ | $S_4$ (as 4T5) | $1$ | $-1$ | |
| 3.2e4_3e4_41e2.4t5.1c1 | $3$ | $ 2^{4} \cdot 3^{4} \cdot 41^{2}$ | $x^{4} - 15 x^{2} - 82 x + 87$ | $S_4$ (as 4T5) | $1$ | $1$ | |
| * | 6.2e10_3e8_41e2.8t34.1c1 | $6$ | $ 2^{10} \cdot 3^{8} \cdot 41^{2}$ | $x^{8} - 2 x^{7} + 2 x^{6} - 4 x^{5} - x^{4} + 22 x^{3} - 28 x^{2} - 16 x + 34$ | $V_4^2:S_3$ (as 8T34) | $1$ | $0$ |
Data is given for all irreducible
representations of the Galois group for the Galois closure
of this field. Those marked with * are summands in the
permutation representation coming from this field. Representations
which appear with multiplicity greater than one are indicated
by exponents on the *.