Normalized defining polynomial
sage: x = polygen(QQ); K.<a> = NumberField(x^16 - 2*x^14 - 8*x^12 + 16*x^10 + 11*x^8 - 18*x^6 + 3*x^4 - x^2 - 1)
gp: K = bnfinit(y^16 - 2*y^14 - 8*y^12 + 16*y^10 + 11*y^8 - 18*y^6 + 3*y^4 - y^2 - 1, 1)
magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^16 - 2*x^14 - 8*x^12 + 16*x^10 + 11*x^8 - 18*x^6 + 3*x^4 - x^2 - 1);
oscar: Qx, x = polynomial_ring(QQ); K, a = number_field(x^16 - 2*x^14 - 8*x^12 + 16*x^10 + 11*x^8 - 18*x^6 + 3*x^4 - x^2 - 1)
\( x^{16} - 2x^{14} - 8x^{12} + 16x^{10} + 11x^{8} - 18x^{6} + 3x^{4} - x^{2} - 1 \)
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: | $[2, 7]$ | sage: K.signature()
gp: K.sign
magma: Signature(K);
oscar: signature(K)
| |
| Discriminant: |
\(-641424792100000000\)
\(\medspace = -\,2^{8}\cdot 5^{8}\cdot 283^{4}\)
| sage: K.disc()
gp: K.disc
magma: OK := Integers(K); Discriminant(OK);
oscar: OK = ring_of_integers(K); discriminant(OK)
| |
| Root discriminant: | \(12.97\) | 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: | $2^{15/8}5^{1/2}283^{1/2}\approx 137.97787808682992$ | ||
| Ramified primes: |
\(2\), \(5\), \(283\)
| sage: K.disc().support()
gp: factor(abs(K.disc))[,1]~
magma: PrimeDivisors(Discriminant(OK));
oscar: prime_divisors(discriminant((OK)))
| |
| Discriminant root field: | \(\Q(\sqrt{-1}) \) | ||
| $\card{ \Aut(K/\Q) }$: | $2$ | 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 \(a\))
$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $\frac{1}{2}a^{12}-\frac{1}{2}a^{11}-\frac{1}{2}a^{10}-\frac{1}{2}a^{9}-\frac{1}{2}a^{7}-\frac{1}{2}a^{5}-\frac{1}{2}a^{3}-\frac{1}{2}a^{2}-\frac{1}{2}$, $\frac{1}{2}a^{13}-\frac{1}{2}a^{9}-\frac{1}{2}a^{8}-\frac{1}{2}a^{7}-\frac{1}{2}a^{6}-\frac{1}{2}a^{5}-\frac{1}{2}a^{4}-\frac{1}{2}a^{2}-\frac{1}{2}a-\frac{1}{2}$, $\frac{1}{3754}a^{14}+\frac{779}{3754}a^{12}-\frac{1}{2}a^{11}-\frac{817}{1877}a^{10}-\frac{1655}{3754}a^{8}+\frac{709}{3754}a^{6}-\frac{2}{1877}a^{4}-\frac{622}{1877}a^{2}-\frac{1}{2}a+\frac{721}{3754}$, $\frac{1}{3754}a^{15}+\frac{779}{3754}a^{13}+\frac{243}{3754}a^{11}-\frac{1}{2}a^{10}+\frac{111}{1877}a^{9}-\frac{584}{1877}a^{7}+\frac{1873}{3754}a^{5}+\frac{633}{3754}a^{3}+\frac{721}{3754}a-\frac{1}{2}$
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: | $8$ | sage: UK.rank()
gp: K.fu
magma: UnitRank(K);
oscar: rank(UK)
| |
| Torsion generator: |
\( -1 \)
(order $2$)
| 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: |
$\frac{84}{1877}a^{14}-\frac{259}{1877}a^{12}-\frac{235}{1877}a^{10}+\frac{1755}{1877}a^{8}-\frac{2385}{1877}a^{6}-\frac{336}{1877}a^{4}+\frac{4370}{1877}a^{2}-\frac{1377}{1877}$, $a$, $\frac{324}{1877}a^{14}-\frac{999}{1877}a^{12}-\frac{1979}{1877}a^{10}+\frac{8110}{1877}a^{8}-\frac{1155}{1877}a^{6}-\frac{10681}{1877}a^{4}+\frac{4253}{1877}a^{2}-\frac{1021}{1877}$, $\frac{1553}{3754}a^{15}+\frac{632}{1877}a^{14}-\frac{2755}{3754}a^{13}-\frac{1323}{1877}a^{12}-\frac{13037}{3754}a^{11}-\frac{10061}{3754}a^{10}+\frac{10961}{1877}a^{9}+\frac{10791}{1877}a^{8}+\frac{10901}{1877}a^{7}+\frac{6993}{1877}a^{6}-\frac{23105}{3754}a^{5}-\frac{13790}{1877}a^{4}-\frac{499}{3754}a^{3}+\frac{255}{1877}a^{2}-\frac{2733}{3754}a+\frac{999}{3754}$, $\frac{1437}{3754}a^{15}-\frac{287}{3754}a^{14}-\frac{3023}{3754}a^{13}-\frac{105}{1877}a^{12}-\frac{11193}{3754}a^{11}+\frac{1731}{1877}a^{10}+\frac{24325}{3754}a^{9}+\frac{1981}{3754}a^{8}+\frac{12761}{3754}a^{7}-\frac{12029}{3754}a^{6}-\frac{14136}{1877}a^{5}-\frac{3180}{1877}a^{4}+\frac{5269}{1877}a^{3}+\frac{6029}{3754}a^{2}-\frac{952}{1877}a-\frac{457}{3754}$, $\frac{633}{1877}a^{15}-\frac{289}{3754}a^{14}-\frac{2965}{3754}a^{13}+\frac{109}{3754}a^{12}-\frac{9575}{3754}a^{11}+\frac{1488}{1877}a^{10}+\frac{23903}{3754}a^{9}-\frac{170}{1877}a^{8}+\frac{9773}{3754}a^{7}-\frac{3908}{1877}a^{6}-\frac{29465}{3754}a^{5}-\frac{4475}{3754}a^{4}+\frac{2765}{1877}a^{3}+\frac{1009}{3754}a^{2}+\frac{282}{1877}a+\frac{1866}{1877}$, $\frac{74}{1877}a^{15}+\frac{335}{1877}a^{14}-\frac{541}{1877}a^{13}-\frac{1753}{3754}a^{12}+\frac{301}{3754}a^{11}-\frac{4243}{3754}a^{10}+\frac{8455}{3754}a^{9}+\frac{6798}{1877}a^{8}-\frac{9565}{3754}a^{7}-\frac{864}{1877}a^{6}-\frac{9977}{3754}a^{5}-\frac{6971}{1877}a^{4}+\frac{9219}{3754}a^{3}+\frac{13047}{3754}a^{2}-\frac{1079}{1877}a-\frac{3073}{3754}$, $\frac{74}{1877}a^{15}-\frac{335}{1877}a^{14}-\frac{541}{1877}a^{13}+\frac{1753}{3754}a^{12}+\frac{301}{3754}a^{11}+\frac{4243}{3754}a^{10}+\frac{8455}{3754}a^{9}-\frac{6798}{1877}a^{8}-\frac{9565}{3754}a^{7}+\frac{864}{1877}a^{6}-\frac{9977}{3754}a^{5}+\frac{6971}{1877}a^{4}+\frac{9219}{3754}a^{3}-\frac{13047}{3754}a^{2}-\frac{1079}{1877}a+\frac{3073}{3754}$
| 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: | \( 222.353266912 \) | sage: K.regulator()
gp: K.reg
magma: Regulator(K);
oscar: regulator(K)
|
Class number formula
\[ \begin{aligned}\lim_{s\to 1} (s-1)\zeta_K(s) =\mathstrut & \frac{2^{r_1}\cdot (2\pi)^{r_2}\cdot R\cdot h}{w\cdot\sqrt{|D|}}\cr \approx\mathstrut &\frac{2^{2}\cdot(2\pi)^{7}\cdot 222.353266912 \cdot 1}{2\cdot\sqrt{641424792100000000}}\cr\approx \mathstrut & 0.214664247218 \end{aligned}\]
# self-contained SageMath code snippet to compute the analytic class number formula
x = polygen(QQ); K.<a> = NumberField(x^16 - 2*x^14 - 8*x^12 + 16*x^10 + 11*x^8 - 18*x^6 + 3*x^4 - 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 - 8*x^12 + 16*x^10 + 11*x^8 - 18*x^6 + 3*x^4 - 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 - 8*x^12 + 16*x^10 + 11*x^8 - 18*x^6 + 3*x^4 - 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 - 8*x^12 + 16*x^10 + 11*x^8 - 18*x^6 + 3*x^4 - 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
$C_{2440}.D_6$ (as 16T1759):
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 12288 |
| The 93 conjugacy class representatives for $C_{2440}.D_6$ |
| Character table for $C_{2440}.D_6$ |
Intermediate fields
| \(\Q(\sqrt{5}) \), 4.2.283.1, 8.4.50055625.1 |
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
| Degree 16 siblings: | data not computed |
| Degree 32 siblings: | data not computed |
| Minimal sibling: | 16.0.262727594844160000.3 |
Frobenius cycle types
| $p$ | $2$ | $3$ | $5$ | $7$ | $11$ | $13$ | $17$ | $19$ | $23$ | $29$ | $31$ | $37$ | $41$ | $43$ | $47$ | $53$ | $59$ |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cycle type | R | ${\href{/padicField/3.8.0.1}{8} }{,}\,{\href{/padicField/3.4.0.1}{4} }^{2}$ | R | ${\href{/padicField/7.12.0.1}{12} }{,}\,{\href{/padicField/7.2.0.1}{2} }^{2}$ | ${\href{/padicField/11.3.0.1}{3} }^{4}{,}\,{\href{/padicField/11.2.0.1}{2} }{,}\,{\href{/padicField/11.1.0.1}{1} }^{2}$ | ${\href{/padicField/13.12.0.1}{12} }{,}\,{\href{/padicField/13.4.0.1}{4} }$ | ${\href{/padicField/17.4.0.1}{4} }^{2}{,}\,{\href{/padicField/17.2.0.1}{2} }^{4}$ | ${\href{/padicField/19.8.0.1}{8} }{,}\,{\href{/padicField/19.4.0.1}{4} }^{2}$ | ${\href{/padicField/23.6.0.1}{6} }^{2}{,}\,{\href{/padicField/23.4.0.1}{4} }$ | ${\href{/padicField/29.6.0.1}{6} }^{2}{,}\,{\href{/padicField/29.2.0.1}{2} }^{2}$ | ${\href{/padicField/31.8.0.1}{8} }{,}\,{\href{/padicField/31.4.0.1}{4} }^{2}$ | ${\href{/padicField/37.4.0.1}{4} }^{2}{,}\,{\href{/padicField/37.2.0.1}{2} }^{4}$ | ${\href{/padicField/41.6.0.1}{6} }{,}\,{\href{/padicField/41.3.0.1}{3} }^{2}{,}\,{\href{/padicField/41.2.0.1}{2} }{,}\,{\href{/padicField/41.1.0.1}{1} }^{2}$ | ${\href{/padicField/43.8.0.1}{8} }{,}\,{\href{/padicField/43.4.0.1}{4} }^{2}$ | ${\href{/padicField/47.8.0.1}{8} }{,}\,{\href{/padicField/47.4.0.1}{4} }^{2}$ | ${\href{/padicField/53.4.0.1}{4} }^{2}{,}\,{\href{/padicField/53.2.0.1}{2} }^{4}$ | ${\href{/padicField/59.3.0.1}{3} }^{4}{,}\,{\href{/padicField/59.2.0.1}{2} }{,}\,{\href{/padicField/59.1.0.1}{1} }^{2}$ |
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 |
|---|---|---|---|---|---|---|---|
|
\(2\)
| 2.4.0.1 | $x^{4} + x + 1$ | $1$ | $4$ | $0$ | $C_4$ | $[\ ]^{4}$ |
| 2.4.0.1 | $x^{4} + x + 1$ | $1$ | $4$ | $0$ | $C_4$ | $[\ ]^{4}$ | |
| 2.8.8.8 | $x^{8} - 6 x^{7} + 40 x^{6} - 52 x^{5} + 192 x^{4} + 328 x^{3} + 1376 x^{2} + 1264 x + 1328$ | $2$ | $4$ | $8$ | $((C_8 : C_2):C_2):C_2$ | $[2, 2, 2, 2]^{4}$ | |
|
\(5\)
| 5.16.8.1 | $x^{16} + 160 x^{15} + 11240 x^{14} + 453600 x^{13} + 11536702 x^{12} + 190484240 x^{11} + 2020220586 x^{10} + 13041178608 x^{9} + 45239382035 x^{8} + 65384309200 x^{7} + 52374358166 x^{6} + 35488260768 x^{5} + 46408266743 x^{4} + 66345171264 x^{3} + 136057926318 x^{2} + 159173865296 x + 74196697609$ | $2$ | $8$ | $8$ | $C_8\times C_2$ | $[\ ]_{2}^{8}$ |
|
\(283\)
| Deg $2$ | $1$ | $2$ | $0$ | $C_2$ | $[\ ]^{2}$ | |
| Deg $2$ | $1$ | $2$ | $0$ | $C_2$ | $[\ ]^{2}$ | ||
| Deg $4$ | $1$ | $4$ | $0$ | $C_4$ | $[\ ]^{4}$ | ||
| Deg $8$ | $2$ | $4$ | $4$ |