Normalized defining polynomial
sage: x = polygen(QQ); K.<a> = NumberField(x^16 - 2*x^14 - 7*x^12 + 4*x^10 + 34*x^8 + 50*x^6 + 32*x^4 + 8*x^2 + 1)
gp: K = bnfinit(y^16 - 2*y^14 - 7*y^12 + 4*y^10 + 34*y^8 + 50*y^6 + 32*y^4 + 8*y^2 + 1, 1)
magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^16 - 2*x^14 - 7*x^12 + 4*x^10 + 34*x^8 + 50*x^6 + 32*x^4 + 8*x^2 + 1);
oscar: Qx, x = PolynomialRing(QQ); K, a = NumberField(x^16 - 2*x^14 - 7*x^12 + 4*x^10 + 34*x^8 + 50*x^6 + 32*x^4 + 8*x^2 + 1)
\( x^{16} - 2x^{14} - 7x^{12} + 4x^{10} + 34x^{8} + 50x^{6} + 32x^{4} + 8x^{2} + 1 \)
sage: K.defining_polynomial()
gp: K.pol
magma: DefiningPolynomial(K);
oscar: defining_polynomial(K)
Invariants
| Degree: | $16$ | sage: K.degree()
gp: poldegree(K.pol)
magma: Degree(K);
oscar: degree(K)
| |
| Signature: | $[0, 8]$ | sage: K.signature()
gp: K.sign
magma: Signature(K);
oscar: signature(K)
| |
| Discriminant: |
\(5572562780160000\)
\(\medspace = 2^{24}\cdot 3^{12}\cdot 5^{4}\)
| sage: K.disc()
gp: K.disc
magma: OK := Integers(K); Discriminant(OK);
oscar: OK = ring_of_integers(K); discriminant(OK)
| |
| Root discriminant: | \(9.64\) | 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: | $2^{3/2}3^{3/4}5^{1/2}\approx 14.416868484808525$ | ||
| Ramified primes: |
\(2\), \(3\), \(5\)
| sage: K.disc().support()
gp: factor(abs(K.disc))[,1]~
magma: PrimeDivisors(Discriminant(OK));
oscar: prime_divisors(discriminant((OK)))
| |
| Discriminant root field: | \(\Q\) | ||
| $\card{ \Aut(K/\Q) }$: | $8$ | 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 \(a\))
$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $\frac{1}{2}a^{8}-\frac{1}{2}a^{6}-\frac{1}{2}$, $\frac{1}{2}a^{9}-\frac{1}{2}a^{7}-\frac{1}{2}a$, $\frac{1}{2}a^{10}-\frac{1}{2}a^{6}-\frac{1}{2}a^{2}-\frac{1}{2}$, $\frac{1}{2}a^{11}-\frac{1}{2}a^{7}-\frac{1}{2}a^{3}-\frac{1}{2}a$, $\frac{1}{4}a^{12}-\frac{1}{4}a^{11}-\frac{1}{4}a^{10}-\frac{1}{4}a^{9}-\frac{1}{4}a^{8}-\frac{1}{2}a^{7}+\frac{1}{4}a^{6}-\frac{1}{2}a^{5}+\frac{1}{4}a^{4}+\frac{1}{4}a^{3}+\frac{1}{4}$, $\frac{1}{4}a^{13}-\frac{1}{4}a^{8}-\frac{1}{4}a^{7}-\frac{1}{4}a^{6}-\frac{1}{4}a^{5}-\frac{1}{2}a^{4}-\frac{1}{4}a^{3}-\frac{1}{2}a^{2}+\frac{1}{4}a+\frac{1}{4}$, $\frac{1}{572}a^{14}+\frac{43}{572}a^{12}-\frac{1}{4}a^{11}+\frac{69}{572}a^{10}+\frac{53}{286}a^{8}-\frac{1}{4}a^{7}+\frac{57}{143}a^{6}+\frac{7}{286}a^{4}-\frac{1}{4}a^{3}+\frac{233}{572}a^{2}-\frac{1}{4}a+\frac{197}{572}$, $\frac{1}{572}a^{15}+\frac{43}{572}a^{13}-\frac{37}{286}a^{11}-\frac{1}{4}a^{10}-\frac{37}{572}a^{9}-\frac{29}{286}a^{7}-\frac{1}{4}a^{6}-\frac{68}{143}a^{5}-\frac{49}{143}a^{3}-\frac{1}{4}a^{2}+\frac{197}{572}a-\frac{1}{4}$
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: | $7$ | sage: UK.rank()
gp: K.fu
magma: UnitRank(K);
oscar: rank(UK)
| |
| Torsion generator: |
\( \frac{19}{143} a^{14} - \frac{41}{143} a^{12} - \frac{119}{143} a^{10} + \frac{167}{286} a^{8} + \frac{1085}{286} a^{6} + \frac{981}{143} a^{4} + \frac{709}{143} a^{2} + \frac{479}{286} \)
(order $12$)
| 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: |
$\frac{136}{143}a^{15}+\frac{67}{286}a^{14}-\frac{1347}{572}a^{13}-\frac{61}{143}a^{12}-\frac{769}{143}a^{11}-\frac{525}{286}a^{10}+\frac{831}{143}a^{9}+\frac{619}{572}a^{8}+\frac{16639}{572}a^{7}+\frac{4669}{572}a^{6}+\frac{20343}{572}a^{5}+\frac{1756}{143}a^{4}+\frac{9635}{572}a^{3}+\frac{2169}{286}a^{2}+\frac{633}{572}a+\frac{801}{572}$, $\frac{56}{143}a^{15}-\frac{5}{44}a^{14}-\frac{166}{143}a^{13}+\frac{5}{44}a^{12}-\frac{989}{572}a^{11}+\frac{51}{44}a^{10}+\frac{502}{143}a^{9}-\frac{1}{22}a^{8}+\frac{6027}{572}a^{7}-\frac{54}{11}a^{6}+\frac{1213}{143}a^{5}-\frac{189}{22}a^{4}+\frac{855}{572}a^{3}-\frac{241}{44}a^{2}-\frac{917}{572}a-\frac{17}{44}$, $\frac{189}{286}a^{15}-\frac{71}{286}a^{14}-\frac{763}{572}a^{13}+\frac{329}{572}a^{12}-\frac{2661}{572}a^{11}+\frac{927}{572}a^{10}+\frac{1601}{572}a^{9}-\frac{519}{286}a^{8}+\frac{13111}{572}a^{7}-\frac{1087}{143}a^{6}+\frac{18591}{572}a^{5}-\frac{5563}{572}a^{4}+\frac{5141}{286}a^{3}-\frac{621}{143}a^{2}+\frac{1393}{572}a-\frac{58}{143}$, $\frac{49}{286}a^{15}+\frac{5}{44}a^{14}-\frac{181}{286}a^{13}-\frac{5}{44}a^{12}-\frac{245}{572}a^{11}-\frac{51}{44}a^{10}+\frac{309}{143}a^{9}+\frac{1}{22}a^{8}+\frac{2181}{572}a^{7}+\frac{54}{11}a^{6}+\frac{57}{143}a^{5}+\frac{189}{22}a^{4}-\frac{2477}{572}a^{3}+\frac{241}{44}a^{2}-\frac{1429}{572}a+\frac{61}{44}$, $\frac{423}{572}a^{15}+\frac{17}{286}a^{14}-\frac{973}{572}a^{13}+\frac{8}{143}a^{12}-\frac{1351}{286}a^{11}-\frac{657}{572}a^{10}+\frac{2653}{572}a^{9}+\frac{43}{143}a^{8}+\frac{3376}{143}a^{7}+\frac{2175}{572}a^{6}+\frac{8395}{286}a^{5}+\frac{1525}{286}a^{4}+\frac{4163}{286}a^{3}+\frac{1201}{572}a^{2}+\frac{677}{572}a-\frac{23}{572}$, $\frac{61}{143}a^{15}+\frac{123}{572}a^{14}-\frac{519}{572}a^{13}-\frac{145}{572}a^{12}-\frac{1611}{572}a^{11}-\frac{1237}{572}a^{10}+\frac{491}{286}a^{9}+\frac{311}{572}a^{8}+\frac{4221}{286}a^{7}+\frac{5307}{572}a^{6}+\frac{11567}{572}a^{5}+\frac{4007}{286}a^{4}+\frac{1486}{143}a^{3}+\frac{4635}{572}a^{2}+\frac{5}{143}a+\frac{159}{143}$, $\frac{128}{143}a^{15}-\frac{575}{286}a^{13}-\frac{1641}{286}a^{11}+\frac{698}{143}a^{9}+\frac{4159}{143}a^{7}+\frac{10877}{286}a^{5}+\frac{2940}{143}a^{3}+\frac{334}{143}a$
| 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: | \( 62.6647388247 \) | sage: K.regulator()
gp: K.reg
magma: Regulator(K);
oscar: regulator(K)
|
Class number formula
\[ \begin{aligned}\lim_{s\to 1} (s-1)\zeta_K(s) =\mathstrut & \frac{2^{r_1}\cdot (2\pi)^{r_2}\cdot R\cdot h}{w\cdot\sqrt{|D|}}\cr \approx\mathstrut &\frac{2^{0}\cdot(2\pi)^{8}\cdot 62.6647388247 \cdot 1}{12\cdot\sqrt{5572562780160000}}\cr\approx \mathstrut & 0.169923501930 \end{aligned}\]
# self-contained SageMath code snippet to compute the analytic class number formula
x = polygen(QQ); K.<a> = NumberField(x^16 - 2*x^14 - 7*x^12 + 4*x^10 + 34*x^8 + 50*x^6 + 32*x^4 + 8*x^2 + 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))))
# self-contained Pari/GP code snippet to compute the analytic class number formula
K = bnfinit(x^16 - 2*x^14 - 7*x^12 + 4*x^10 + 34*x^8 + 50*x^6 + 32*x^4 + 8*x^2 + 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)))]
/* self-contained Magma code snippet to compute the analytic class number formula */
Qx<x> := PolynomialRing(QQ); K<a> := NumberField(x^16 - 2*x^14 - 7*x^12 + 4*x^10 + 34*x^8 + 50*x^6 + 32*x^4 + 8*x^2 + 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)));
# self-contained Oscar code snippet to compute the analytic class number formula
Qx, x = PolynomialRing(QQ); K, a = NumberField(x^16 - 2*x^14 - 7*x^12 + 4*x^10 + 34*x^8 + 50*x^6 + 32*x^4 + 8*x^2 + 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
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 32 |
| The 14 conjugacy class representatives for $C_4:D_4$ |
| Character table for $C_4:D_4$ |
Intermediate fields
| \(\Q(\sqrt{-1}) \), \(\Q(\sqrt{3}) \), \(\Q(\sqrt{-3}) \), 4.0.320.1, 4.0.2880.1, 4.0.432.1 x2, 4.2.1728.1 x2, \(\Q(\zeta_{12})\), 8.0.2985984.1, 8.0.4665600.1, 8.0.8294400.2 |
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
| Galois closure: | deg 32 |
| Degree 16 siblings: | 16.0.3482851737600000000.1, 16.0.217678233600000000.2, 16.4.3482851737600000000.1 |
| Minimal sibling: | 16.0.217678233600000000.2 |
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 | R | ${\href{/padicField/7.4.0.1}{4} }^{4}$ | ${\href{/padicField/11.2.0.1}{2} }^{8}$ | ${\href{/padicField/13.2.0.1}{2} }^{8}$ | ${\href{/padicField/17.4.0.1}{4} }^{4}$ | ${\href{/padicField/19.2.0.1}{2} }^{8}$ | ${\href{/padicField/23.4.0.1}{4} }^{4}$ | ${\href{/padicField/29.4.0.1}{4} }^{4}$ | ${\href{/padicField/31.2.0.1}{2} }^{8}$ | ${\href{/padicField/37.2.0.1}{2} }^{4}{,}\,{\href{/padicField/37.1.0.1}{1} }^{8}$ | ${\href{/padicField/41.4.0.1}{4} }^{4}$ | ${\href{/padicField/43.4.0.1}{4} }^{4}$ | ${\href{/padicField/47.4.0.1}{4} }^{4}$ | ${\href{/padicField/53.4.0.1}{4} }^{4}$ | ${\href{/padicField/59.2.0.1}{2} }^{8}$ |
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
| $p$ | Label | Polynomial | $e$ | $f$ | $c$ | Galois group | Slope content |
|---|---|---|---|---|---|---|---|
|
\(2\)
| Deg $16$ | $4$ | $4$ | $24$ | |||
|
\(3\)
| 3.16.12.1 | $x^{16} + 8 x^{15} + 24 x^{14} + 32 x^{13} + 36 x^{12} + 120 x^{11} + 312 x^{10} + 352 x^{9} - 522 x^{8} - 2664 x^{7} - 3672 x^{6} - 1440 x^{5} + 4292 x^{4} + 7720 x^{3} + 6408 x^{2} + 2592 x + 433$ | $4$ | $4$ | $12$ | $C_4:C_4$ | $[\ ]_{4}^{4}$ |
|
\(5\)
| 5.4.0.1 | $x^{4} + 4 x^{2} + 4 x + 2$ | $1$ | $4$ | $0$ | $C_4$ | $[\ ]^{4}$ |
| 5.4.0.1 | $x^{4} + 4 x^{2} + 4 x + 2$ | $1$ | $4$ | $0$ | $C_4$ | $[\ ]^{4}$ | |
| 5.8.4.1 | $x^{8} + 80 x^{7} + 2428 x^{6} + 33688 x^{5} + 195810 x^{4} + 305952 x^{3} + 870132 x^{2} + 1037416 x + 503089$ | $2$ | $4$ | $4$ | $C_4\times C_2$ | $[\ ]_{2}^{4}$ |