↑

Properties

Label 7.1.364871.1
Degree $7$
Signature $(1, 3)$
Discriminant $-364871$
Root discriminant \(6.23\)
Ramified primes $13,17,127$
Class number $1$
Class group trivial
Galois group $S_7$ (as 7T7)

Related objects

Downloads

Learn more

Show commands: Magma / Oscar / Pari/GP / SageMath

Normalized defining polynomial

Copy content comment:Define the number field
 
Copy content sage:x = polygen(QQ); K.<a> = NumberField(x^7 - x^6 + 2*x^4 + 2*x + 1)
 
Copy content gp:K = bnfinit(y^7 - y^6 + 2*y^4 + 2*y + 1, 1)
 
Copy content magma:R<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^7 - x^6 + 2*x^4 + 2*x + 1);
 
Copy content oscar:Qx, x = polynomial_ring(QQ); K, a = number_field(x^7 - x^6 + 2*x^4 + 2*x + 1)
 

\( x^{7} - x^{6} + 2x^{4} + 2x + 1 \) 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:  $7$
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:  $(1, 3)$
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:   \(-364871\) \(\medspace = -\,13^{2}\cdot 17\cdot 127\) 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:  \(6.23\)
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:  $13^{1/2}17^{1/2}127^{1/2}\approx 167.5320864789787$
Ramified primes:   \(13\), \(17\), \(127\) 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:  \(\Q(\sqrt{-2159}) \)
$\Aut(K/\Q)$:   $C_1$
Copy content comment:Autmorphisms
 
Copy content sage:K.automorphisms()
 
Copy content magma:Automorphisms(K);
 
Copy content oscar:automorphism_group(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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$ 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:  Yes
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:  Trivial group, which has order $1$
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:  $3$
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:   $a^{6}-a^{5}+2a^{3}-a^{2}+a+2$, $a$, $a^{6}-2a^{5}+a^{4}+2a^{3}-2a^{2}+2$ 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:  \( 0.631311355925 \)
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

\[ \begin{aligned}\lim_{s\to 1} (s-1)\zeta_K(s) =\mathstrut & \frac{2^{r_1}\cdot (2\pi)^{r_2}\cdot R\cdot h}{w\cdot\sqrt{|D|}}\cr \approx\mathstrut &\frac{2^{1}\cdot(2\pi)^{3}\cdot 0.631311355925 \cdot 1}{2\cdot\sqrt{364871}}\cr\approx \mathstrut & 0.2592468767746 \end{aligned}\]

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^7 - x^6 + 2*x^4 + 2*x + 1) 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^7 - x^6 + 2*x^4 + 2*x + 1, 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^7 - x^6 + 2*x^4 + 2*x + 1); 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^7 - x^6 + 2*x^4 + 2*x + 1); 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

$S_7$ (as 7T7):

Copy content comment:Galois group
 
Copy content sage:K.galois_group()
 
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 non-solvable group of order 5040
The 15 conjugacy class representatives for $S_7$
Character table for $S_7$

Intermediate fields

The extension is primitive: there are no intermediate fields between this field and $\Q$.
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

Degree 14 sibling: deg 14
Degree 21 sibling: deg 21
Degree 30 sibling: deg 30
Degree 35 sibling: deg 35
Degree 42 siblings: deg 42, deg 42, deg 42, some 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 ${\href{/padicField/2.7.0.1}{7} }$ ${\href{/padicField/3.7.0.1}{7} }$ ${\href{/padicField/5.4.0.1}{4} }{,}\,{\href{/padicField/5.2.0.1}{2} }{,}\,{\href{/padicField/5.1.0.1}{1} }$ ${\href{/padicField/7.7.0.1}{7} }$ ${\href{/padicField/11.4.0.1}{4} }{,}\,{\href{/padicField/11.3.0.1}{3} }$ R R ${\href{/padicField/19.3.0.1}{3} }^{2}{,}\,{\href{/padicField/19.1.0.1}{1} }$ ${\href{/padicField/23.7.0.1}{7} }$ ${\href{/padicField/29.7.0.1}{7} }$ ${\href{/padicField/31.6.0.1}{6} }{,}\,{\href{/padicField/31.1.0.1}{1} }$ ${\href{/padicField/37.6.0.1}{6} }{,}\,{\href{/padicField/37.1.0.1}{1} }$ ${\href{/padicField/41.6.0.1}{6} }{,}\,{\href{/padicField/41.1.0.1}{1} }$ ${\href{/padicField/43.6.0.1}{6} }{,}\,{\href{/padicField/43.1.0.1}{1} }$ ${\href{/padicField/47.5.0.1}{5} }{,}\,{\href{/padicField/47.1.0.1}{1} }^{2}$ ${\href{/padicField/53.4.0.1}{4} }{,}\,{\href{/padicField/53.3.0.1}{3} }$ ${\href{/padicField/59.4.0.1}{4} }{,}\,{\href{/padicField/59.1.0.1}{1} }^{3}$

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
\(13\) Copy content Toggle raw display $\Q_{13}$$x + 11$$1$$1$$0$Trivial$$[\ ]$$
13.2.1.0a1.1$x^{2} + 12 x + 2$$1$$2$$0$$C_2$$$[\ ]^{2}$$
13.2.2.2a1.1$x^{4} + 24 x^{3} + 148 x^{2} + 61 x + 4$$2$$2$$2$$C_4$$$[\ ]_{2}^{2}$$
\(17\) Copy content Toggle raw display 17.1.2.1a1.1$x^{2} + 17$$2$$1$$1$$C_2$$$[\ ]_{2}$$
17.5.1.0a1.1$x^{5} + x + 14$$1$$5$$0$$C_5$$$[\ ]^{5}$$
\(127\) Copy content Toggle raw display $\Q_{127}$$x + 124$$1$$1$$0$Trivial$$[\ ]$$
127.1.2.1a1.2$x^{2} + 381$$2$$1$$1$$C_2$$$[\ ]_{2}$$
127.4.1.0a1.1$x^{4} + 2 x^{2} + 97 x + 3$$1$$4$$0$$C_4$$$[\ ]^{4}$$

Artin representations

Label Dimension Conductor Artin stem field $G$ Ind $\chi(c)$
*5040 1.1.1t1.a.a$1$ $1$ \(\Q\) $C_1$ $1$ $1$
1.2159.2t1.a.a$1$ $ 17 \cdot 127 $ \(\Q(\sqrt{-2159}) \) $C_2$ (as 2T1) $1$ $-1$
6.792...031.14t46.a.a$6$ $ 13^{2} \cdot 17^{5} \cdot 127^{5}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $0$
*5040 6.364871.7t7.a.a$6$ $ 13^{2} \cdot 17 \cdot 127 $ 7.1.364871.1 $S_7$ (as 7T7) $1$ $0$
14.104...449.21t38.a.a$14$ $ 13^{6} \cdot 17^{4} \cdot 127^{4}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $2$
14.106...409.42t413.a.a$14$ $ 13^{6} \cdot 17^{10} \cdot 127^{10}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $-2$
14.491...751.30t565.a.a$14$ $ 13^{6} \cdot 17^{9} \cdot 127^{9}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $0$
14.226...391.30t565.a.a$14$ $ 13^{6} \cdot 17^{5} \cdot 127^{5}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $0$
15.382...079.42t412.a.a$15$ $ 13^{8} \cdot 17^{5} \cdot 127^{5}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $-3$
15.179...121.42t411.a.a$15$ $ 13^{8} \cdot 17^{10} \cdot 127^{10}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $3$
20.512...881.70.a.a$20$ $ 13^{12} \cdot 17^{10} \cdot 127^{10}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $0$
21.303...449.84.a.a$21$ $ 13^{10} \cdot 17^{10} \cdot 127^{10}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $-3$
21.654...391.42t418.a.a$21$ $ 13^{10} \cdot 17^{11} \cdot 127^{11}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $3$
35.544...329.126.a.a$35$ $ 13^{18} \cdot 17^{20} \cdot 127^{20}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $-1$
35.116...471.70.a.a$35$ $ 13^{18} \cdot 17^{15} \cdot 127^{15}$ 7.1.364871.1 $S_7$ (as 7T7) $1$ $1$

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 *.

Spectrum of ring of integers

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