Properties

Label 15.5.804...000.1
Degree $15$
Signature $[5, 5]$
Discriminant $-8.045\times 10^{20}$
Root discriminant \(24.76\)
Ramified primes $2,5,23$
Class number $1$ (GRH)
Class group trivial (GRH)
Galois group $D_5^3.D_6$ (as 15T68)

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Show commands: Magma / Oscar / PariGP / SageMath

Normalized defining polynomial

sage: x = polygen(QQ); K.<a> = NumberField(x^15 - 15*x^13 + 90*x^11 - 2*x^10 - 275*x^9 + 20*x^8 + 450*x^7 - 70*x^6 - 375*x^5 + 100*x^4 + 125*x^3 - 50*x^2 + 8)
 
gp: K = bnfinit(y^15 - 15*y^13 + 90*y^11 - 2*y^10 - 275*y^9 + 20*y^8 + 450*y^7 - 70*y^6 - 375*y^5 + 100*y^4 + 125*y^3 - 50*y^2 + 8, 1)
 
magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^15 - 15*x^13 + 90*x^11 - 2*x^10 - 275*x^9 + 20*x^8 + 450*x^7 - 70*x^6 - 375*x^5 + 100*x^4 + 125*x^3 - 50*x^2 + 8);
 
oscar: Qx, x = PolynomialRing(QQ); K, a = NumberField(x^15 - 15*x^13 + 90*x^11 - 2*x^10 - 275*x^9 + 20*x^8 + 450*x^7 - 70*x^6 - 375*x^5 + 100*x^4 + 125*x^3 - 50*x^2 + 8)
 

\( x^{15} - 15 x^{13} + 90 x^{11} - 2 x^{10} - 275 x^{9} + 20 x^{8} + 450 x^{7} - 70 x^{6} - 375 x^{5} + \cdots + 8 \) Copy content Toggle raw display

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

Invariants

Degree:  $15$
sage: K.degree()
 
gp: poldegree(K.pol)
 
magma: Degree(K);
 
oscar: degree(K)
 
Signature:  $[5, 5]$
sage: K.signature()
 
gp: K.sign
 
magma: Signature(K);
 
oscar: signature(K)
 
Discriminant:   \(-804542875000000000000\) \(\medspace = -\,2^{12}\cdot 5^{15}\cdot 23^{5}\) Copy content Toggle raw display
sage: K.disc()
 
gp: K.disc
 
magma: OK := Integers(K); Discriminant(OK);
 
oscar: OK = ring_of_integers(K); discriminant(OK)
 
Root discriminant:  \(24.76\)
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:  not computed
Ramified primes:   \(2\), \(5\), \(23\) Copy content Toggle raw display
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
magma: PrimeDivisors(Discriminant(OK));
 
oscar: prime_divisors(discriminant((OK)))
 
Discriminant root field:  \(\Q(\sqrt{-115}) \)
$\card{ \Aut(K/\Q) }$:  $1$
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 \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $\frac{1}{2}a^{5}-\frac{1}{2}a^{3}-\frac{1}{2}a$, $\frac{1}{2}a^{6}-\frac{1}{2}a^{4}-\frac{1}{2}a^{2}$, $\frac{1}{2}a^{7}-\frac{1}{2}a$, $\frac{1}{2}a^{8}-\frac{1}{2}a^{2}$, $\frac{1}{2}a^{9}-\frac{1}{2}a^{3}$, $\frac{1}{4}a^{10}-\frac{1}{4}a^{6}-\frac{1}{2}a^{4}-\frac{1}{4}a^{2}$, $\frac{1}{4}a^{11}-\frac{1}{4}a^{7}+\frac{1}{4}a^{3}-\frac{1}{2}a$, $\frac{1}{4}a^{12}-\frac{1}{4}a^{8}+\frac{1}{4}a^{4}-\frac{1}{2}a^{2}$, $\frac{1}{4}a^{13}-\frac{1}{4}a^{9}-\frac{1}{4}a^{5}-\frac{1}{2}a$, $\frac{1}{4}a^{14}-\frac{1}{4}a^{2}$ Copy content Toggle raw display

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 $1$ (assuming GRH)

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:  $9$
sage: UK.rank()
 
gp: K.fu
 
magma: UnitRank(K);
 
oscar: rank(UK)
 
Torsion generator:   \( -1 \)  (order $2$) Copy content Toggle raw display
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:   $\frac{1}{2}a^{5}+\frac{5}{2}a^{3}-\frac{5}{2}a$, $\frac{1}{4}a^{13}-3a^{11}+\frac{55}{4}a^{9}-\frac{1}{2}a^{8}-30a^{7}+\frac{7}{2}a^{6}+\frac{125}{4}a^{5}-\frac{15}{2}a^{4}-\frac{25}{2}a^{3}+5a^{2}-1$, $\frac{1}{4}a^{13}-\frac{1}{4}a^{12}+\frac{13}{4}a^{11}+\frac{13}{4}a^{10}-\frac{65}{4}a^{9}-\frac{63}{4}a^{8}+\frac{159}{4}a^{7}+\frac{141}{4}a^{6}-\frac{205}{4}a^{5}-\frac{149}{4}a^{4}+\frac{141}{4}a^{3}+\frac{71}{4}a^{2}-\frac{19}{2}a-3$, $\frac{1}{4}a^{11}+3a^{9}-\frac{55}{4}a^{7}+\frac{1}{2}a^{6}+30a^{5}-\frac{7}{2}a^{4}-\frac{125}{4}a^{3}+\frac{15}{2}a^{2}+\frac{25}{2}a-5$, $\frac{1}{4}a^{11}-3a^{9}+\frac{55}{4}a^{7}-\frac{1}{2}a^{6}-30a^{5}+\frac{7}{2}a^{4}+\frac{125}{4}a^{3}-\frac{15}{2}a^{2}-\frac{25}{2}a+4$, $\frac{1}{4}a^{14}-\frac{1}{4}a^{13}-\frac{7}{2}a^{12}+\frac{7}{2}a^{11}+19a^{10}-\frac{77}{4}a^{9}-\frac{99}{2}a^{8}+\frac{105}{2}a^{7}+60a^{6}-\frac{289}{4}a^{5}-\frac{43}{2}a^{4}+\frac{83}{2}a^{3}-\frac{41}{4}a^{2}-a+2$, $\frac{1}{4}a^{14}+\frac{15}{4}a^{12}+\frac{1}{4}a^{11}-\frac{45}{2}a^{10}-\frac{5}{2}a^{9}+\frac{275}{4}a^{8}+\frac{35}{4}a^{7}-113a^{6}-13a^{5}+\frac{389}{4}a^{4}+\frac{39}{4}a^{3}-\frac{151}{4}a^{2}-\frac{13}{2}a+2$, $\frac{1}{4}a^{12}-\frac{13}{4}a^{10}+\frac{1}{2}a^{9}+\frac{63}{4}a^{8}-\frac{9}{2}a^{7}-\frac{141}{4}a^{6}+\frac{29}{2}a^{5}+\frac{145}{4}a^{4}-20a^{3}-\frac{51}{4}a^{2}+9a-1$, $\frac{1}{2}a^{7}+\frac{1}{2}a^{6}-3a^{5}-\frac{5}{2}a^{4}+5a^{3}+\frac{5}{2}a^{2}-\frac{5}{2}a+1$ Copy content Toggle raw display (assuming GRH)
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:  \( 59566.61941447335 \) (assuming GRH)
sage: K.regulator()
 
gp: K.reg
 
magma: Regulator(K);
 
oscar: regulator(K)
 

Class number formula

\[ \begin{aligned}\lim_{s\to 1} (s-1)\zeta_K(s) =\mathstrut & \frac{2^{r_1}\cdot (2\pi)^{r_2}\cdot R\cdot h}{w\cdot\sqrt{|D|}}\cr \approx\mathstrut &\frac{2^{5}\cdot(2\pi)^{5}\cdot 59566.61941447335 \cdot 1}{2\cdot\sqrt{804542875000000000000}}\cr\approx \mathstrut & 0.329039230745383 \end{aligned}\] (assuming GRH)

# self-contained SageMath code snippet to compute the analytic class number formula
 
x = polygen(QQ); K.<a> = NumberField(x^15 - 15*x^13 + 90*x^11 - 2*x^10 - 275*x^9 + 20*x^8 + 450*x^7 - 70*x^6 - 375*x^5 + 100*x^4 + 125*x^3 - 50*x^2 + 8)
 
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^15 - 15*x^13 + 90*x^11 - 2*x^10 - 275*x^9 + 20*x^8 + 450*x^7 - 70*x^6 - 375*x^5 + 100*x^4 + 125*x^3 - 50*x^2 + 8, 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^15 - 15*x^13 + 90*x^11 - 2*x^10 - 275*x^9 + 20*x^8 + 450*x^7 - 70*x^6 - 375*x^5 + 100*x^4 + 125*x^3 - 50*x^2 + 8);
 
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^15 - 15*x^13 + 90*x^11 - 2*x^10 - 275*x^9 + 20*x^8 + 450*x^7 - 70*x^6 - 375*x^5 + 100*x^4 + 125*x^3 - 50*x^2 + 8);
 
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

$D_5^3.D_6$ (as 15T68):

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 12000
The 38 conjugacy class representatives for $D_5^3.D_6$
Character table for $D_5^3.D_6$

Intermediate fields

3.1.23.1

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 20 sibling: data not computed
Degree 30 siblings: data not computed
Degree 40 siblings: 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 R ${\href{/padicField/3.12.0.1}{12} }{,}\,{\href{/padicField/3.3.0.1}{3} }$ R ${\href{/padicField/7.4.0.1}{4} }{,}\,{\href{/padicField/7.2.0.1}{2} }^{5}{,}\,{\href{/padicField/7.1.0.1}{1} }$ ${\href{/padicField/11.5.0.1}{5} }{,}\,{\href{/padicField/11.4.0.1}{4} }^{2}{,}\,{\href{/padicField/11.2.0.1}{2} }$ ${\href{/padicField/13.12.0.1}{12} }{,}\,{\href{/padicField/13.3.0.1}{3} }$ ${\href{/padicField/17.4.0.1}{4} }{,}\,{\href{/padicField/17.2.0.1}{2} }^{5}{,}\,{\href{/padicField/17.1.0.1}{1} }$ ${\href{/padicField/19.10.0.1}{10} }{,}\,{\href{/padicField/19.5.0.1}{5} }$ R ${\href{/padicField/29.6.0.1}{6} }^{2}{,}\,{\href{/padicField/29.3.0.1}{3} }$ ${\href{/padicField/31.6.0.1}{6} }^{2}{,}\,{\href{/padicField/31.3.0.1}{3} }$ ${\href{/padicField/37.10.0.1}{10} }{,}\,{\href{/padicField/37.4.0.1}{4} }{,}\,{\href{/padicField/37.1.0.1}{1} }$ $15$ ${\href{/padicField/43.4.0.1}{4} }^{3}{,}\,{\href{/padicField/43.2.0.1}{2} }{,}\,{\href{/padicField/43.1.0.1}{1} }$ ${\href{/padicField/47.12.0.1}{12} }{,}\,{\href{/padicField/47.3.0.1}{3} }$ ${\href{/padicField/53.4.0.1}{4} }^{3}{,}\,{\href{/padicField/53.2.0.1}{2} }{,}\,{\href{/padicField/53.1.0.1}{1} }$ ${\href{/padicField/59.5.0.1}{5} }{,}\,{\href{/padicField/59.2.0.1}{2} }^{4}{,}\,{\href{/padicField/59.1.0.1}{1} }^{2}$

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

$p$LabelPolynomial $e$ $f$ $c$ Galois group Slope content
\(2\) Copy content Toggle raw display 2.3.0.1$x^{3} + x + 1$$1$$3$$0$$C_3$$[\ ]^{3}$
2.12.12.12$x^{12} + 84 x^{10} - 88 x^{9} + 1660 x^{8} - 1568 x^{7} + 13920 x^{6} - 4928 x^{5} + 47280 x^{4} + 23936 x^{3} + 63552 x^{2} + 32896 x + 51520$$2$$6$$12$12T29$[2, 2, 2]^{6}$
\(5\) Copy content Toggle raw display 5.5.5.1$x^{5} + 20 x + 5$$5$$1$$5$$F_5$$[5/4]_{4}$
5.10.10.14$x^{10} + 10 x^{6} + 10 x^{5} - 25 x^{2} + 50 x + 25$$5$$2$$10$$(C_5^2 : C_4) : C_2$$[5/4, 5/4]_{4}^{2}$
\(23\) Copy content Toggle raw display $\Q_{23}$$x + 18$$1$$1$$0$Trivial$[\ ]$
23.2.1.2$x^{2} + 23$$2$$1$$1$$C_2$$[\ ]_{2}$
23.4.0.1$x^{4} + 3 x^{2} + 19 x + 5$$1$$4$$0$$C_4$$[\ ]^{4}$
23.8.4.1$x^{8} + 98 x^{6} + 38 x^{5} + 3331 x^{4} - 1634 x^{3} + 44919 x^{2} - 57494 x + 224528$$2$$4$$4$$C_4\times C_2$$[\ ]_{2}^{4}$