Properties

Label 40.0.37371137649...7536.1
Degree $40$
Signature $[0, 20]$
Discriminant $2^{80}\cdot 11^{36}$
Root discriminant $34.62$
Ramified primes $2, 11$
Class number $55$ (GRH)
Class group $[55]$ (GRH)
Galois group $C_2^2\times C_{10}$ (as 40T7)

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Show commands for: Magma / SageMath / Pari/GP

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1]);
 
sage: x = polygen(QQ); K.<a> = NumberField(x^40 - x^36 + x^32 - x^28 + x^24 - x^20 + x^16 - x^12 + x^8 - x^4 + 1)
 
gp: K = bnfinit(x^40 - x^36 + x^32 - x^28 + x^24 - x^20 + x^16 - x^12 + x^8 - x^4 + 1, 1)
 

Normalized defining polynomial

\( x^{40} - x^{36} + x^{32} - x^{28} + x^{24} - x^{20} + x^{16} - x^{12} + x^{8} - x^{4} + 1 \)

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

Invariants

Degree:  $40$
magma: Degree(K);
 
sage: K.degree()
 
gp: poldegree(K.pol)
 
Signature:  $[0, 20]$
magma: Signature(K);
 
sage: K.signature()
 
gp: K.sign
 
Discriminant:  \(37371137649685869661036271274571515833850102932794388078657536=2^{80}\cdot 11^{36}\)
magma: Discriminant(Integers(K));
 
sage: K.disc()
 
gp: K.disc
 
Root discriminant:  $34.62$
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:  $2, 11$
magma: PrimeDivisors(Discriminant(Integers(K)));
 
sage: K.disc().support()
 
gp: factor(abs(K.disc))[,1]~
 
This field is Galois and abelian over $\Q$.
Conductor:  \(88=2^{3}\cdot 11\)
Dirichlet character group:    $\lbrace$$\chi_{88}(1,·)$, $\chi_{88}(3,·)$, $\chi_{88}(5,·)$, $\chi_{88}(7,·)$, $\chi_{88}(9,·)$, $\chi_{88}(13,·)$, $\chi_{88}(15,·)$, $\chi_{88}(17,·)$, $\chi_{88}(19,·)$, $\chi_{88}(21,·)$, $\chi_{88}(23,·)$, $\chi_{88}(25,·)$, $\chi_{88}(27,·)$, $\chi_{88}(29,·)$, $\chi_{88}(31,·)$, $\chi_{88}(35,·)$, $\chi_{88}(37,·)$, $\chi_{88}(39,·)$, $\chi_{88}(41,·)$, $\chi_{88}(43,·)$, $\chi_{88}(45,·)$, $\chi_{88}(47,·)$, $\chi_{88}(49,·)$, $\chi_{88}(51,·)$, $\chi_{88}(53,·)$, $\chi_{88}(57,·)$, $\chi_{88}(59,·)$, $\chi_{88}(61,·)$, $\chi_{88}(63,·)$, $\chi_{88}(65,·)$, $\chi_{88}(67,·)$, $\chi_{88}(69,·)$, $\chi_{88}(71,·)$, $\chi_{88}(73,·)$, $\chi_{88}(75,·)$, $\chi_{88}(79,·)$, $\chi_{88}(81,·)$, $\chi_{88}(83,·)$, $\chi_{88}(85,·)$, $\chi_{88}(87,·)$$\rbrace$
This is a CM field.

Integral basis (with respect to field generator \(a\))

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $a^{15}$, $a^{16}$, $a^{17}$, $a^{18}$, $a^{19}$, $a^{20}$, $a^{21}$, $a^{22}$, $a^{23}$, $a^{24}$, $a^{25}$, $a^{26}$, $a^{27}$, $a^{28}$, $a^{29}$, $a^{30}$, $a^{31}$, $a^{32}$, $a^{33}$, $a^{34}$, $a^{35}$, $a^{36}$, $a^{37}$, $a^{38}$, $a^{39}$

magma: IntegralBasis(K);
 
sage: K.integral_basis()
 
gp: K.zk
 

Class group and class number

$C_{55}$, which has order $55$ (assuming GRH)

magma: ClassGroup(K);
 
sage: K.class_group().invariants()
 
gp: K.clgp
 

Unit group

magma: UK, f := UnitGroup(K);
 
sage: UK = K.unit_group()
 
Rank:  $19$
magma: UnitRank(K);
 
sage: UK.rank()
 
gp: K.fu
 
Torsion generator:  \( a \) (order $88$)
magma: K!f(TU.1) where TU,f is TorsionUnitGroup(K);
 
sage: UK.torsion_generator()
 
gp: K.tu[2]
 
Fundamental units:  \( a^{8} + 1 \),  \( a^{16} + 1 \),  \( a^{16} + a^{8} + 1 \),  \( a^{8} - a^{4} \),  \( a^{6} - 1 \),  \( a^{18} - 1 \),  \( a^{10} - 1 \),  \( a^{14} - 1 \),  \( a^{3} - 1 \),  \( a^{15} - 1 \),  \( a^{5} - 1 \),  \( a^{9} - 1 \),  \( a^{17} - 1 \),  \( a^{7} - 1 \),  \( a - 1 \),  \( a^{7} + a^{6} \),  \( a^{13} - 1 \),  \( a^{22} + a^{11} + 1 \),  \( a^{19} - 1 \) (assuming GRH)
magma: [K!f(g): g in Generators(UK)];
 
sage: UK.fundamental_units()
 
gp: K.fu
 
Regulator:  \( 172972974175441.34 \) (assuming GRH)
magma: Regulator(K);
 
sage: K.regulator()
 
gp: K.reg
 

Galois group

$C_2^2\times C_{10}$ (as 40T7):

magma: GaloisGroup(K);
 
sage: K.galois_group(type='pari')
 
gp: polgalois(K.pol)
 
An abelian group of order 40
The 40 conjugacy class representatives for $C_2^2\times C_{10}$
Character table for $C_2^2\times C_{10}$ is not computed

Intermediate fields

\(\Q(\sqrt{2}) \), \(\Q(\sqrt{-1}) \), \(\Q(\sqrt{-2}) \), \(\Q(\sqrt{-11}) \), \(\Q(\sqrt{-22}) \), \(\Q(\sqrt{11}) \), \(\Q(\sqrt{22}) \), \(\Q(\zeta_{8})\), \(\Q(\sqrt{2}, \sqrt{-11})\), \(\Q(\sqrt{2}, \sqrt{11})\), \(\Q(i, \sqrt{11})\), \(\Q(i, \sqrt{22})\), \(\Q(\sqrt{-2}, \sqrt{-11})\), \(\Q(\sqrt{-2}, \sqrt{11})\), \(\Q(\zeta_{11})^+\), 8.0.959512576.1, 10.10.7024111812608.1, 10.0.219503494144.1, 10.0.7024111812608.1, \(\Q(\zeta_{11})\), 10.0.77265229938688.1, \(\Q(\zeta_{44})^+\), 10.10.77265229938688.1, 20.0.50522262278163705147147943936.1, 20.0.5969915757478328440239161344.6, \(\Q(\zeta_{88})^+\), \(\Q(\zeta_{44})\), 20.0.6113193735657808322804901216256.4, 20.0.5969915757478328440239161344.5, 20.0.6113193735657808322804901216256.3

Fields in the database are given up to isomorphism. Isomorphic intermediate fields are shown with their multiplicities.

Frobenius cycle types

$p$ 2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59
Cycle type R ${\href{/LocalNumberField/3.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/5.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/7.10.0.1}{10} }^{4}$ R ${\href{/LocalNumberField/13.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/17.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/19.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/23.2.0.1}{2} }^{20}$ ${\href{/LocalNumberField/29.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/31.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/37.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/41.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/43.2.0.1}{2} }^{20}$ ${\href{/LocalNumberField/47.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/53.10.0.1}{10} }^{4}$ ${\href{/LocalNumberField/59.10.0.1}{10} }^{4}$

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

$p$LabelPolynomial $e$ $f$ $c$ Galois group Slope content
2Data not computed
11Data not computed