Properties

Label 42.0.742...504.1
Degree $42$
Signature $[0, 21]$
Discriminant $-7.425\times 10^{76}$
Root discriminant \(67.65\)
Ramified primes $2,7$
Class number $1923461$ (GRH)
Class group [1923461] (GRH)
Galois group $C_{42}$ (as 42T1)

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Normalized defining polynomial

sage: x = polygen(QQ); K.<a> = NumberField(x^42 + 42*x^40 + 819*x^38 + 9842*x^36 + 81585*x^34 + 494802*x^32 + 2272424*x^30 + 8069423*x^28 + 22428224*x^26 + 49085050*x^24 + 84669739*x^22 + 114704933*x^20 + 121049551*x^18 + 98190708*x^16 + 60019861*x^14 + 26865216*x^12 + 8444436*x^10 + 1749188*x^8 + 215453*x^6 + 13181*x^4 + 294*x^2 + 1)
 
gp: K = bnfinit(y^42 + 42*y^40 + 819*y^38 + 9842*y^36 + 81585*y^34 + 494802*y^32 + 2272424*y^30 + 8069423*y^28 + 22428224*y^26 + 49085050*y^24 + 84669739*y^22 + 114704933*y^20 + 121049551*y^18 + 98190708*y^16 + 60019861*y^14 + 26865216*y^12 + 8444436*y^10 + 1749188*y^8 + 215453*y^6 + 13181*y^4 + 294*y^2 + 1, 1)
 
magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(x^42 + 42*x^40 + 819*x^38 + 9842*x^36 + 81585*x^34 + 494802*x^32 + 2272424*x^30 + 8069423*x^28 + 22428224*x^26 + 49085050*x^24 + 84669739*x^22 + 114704933*x^20 + 121049551*x^18 + 98190708*x^16 + 60019861*x^14 + 26865216*x^12 + 8444436*x^10 + 1749188*x^8 + 215453*x^6 + 13181*x^4 + 294*x^2 + 1);
 
oscar: Qx, x = PolynomialRing(QQ); K, a = NumberField(x^42 + 42*x^40 + 819*x^38 + 9842*x^36 + 81585*x^34 + 494802*x^32 + 2272424*x^30 + 8069423*x^28 + 22428224*x^26 + 49085050*x^24 + 84669739*x^22 + 114704933*x^20 + 121049551*x^18 + 98190708*x^16 + 60019861*x^14 + 26865216*x^12 + 8444436*x^10 + 1749188*x^8 + 215453*x^6 + 13181*x^4 + 294*x^2 + 1)
 

\( x^{42} + 42 x^{40} + 819 x^{38} + 9842 x^{36} + 81585 x^{34} + 494802 x^{32} + 2272424 x^{30} + 8069423 x^{28} + \cdots + 1 \) Copy content Toggle raw display

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

Invariants

Degree:  $42$
sage: K.degree()
 
gp: poldegree(K.pol)
 
magma: Degree(K);
 
oscar: degree(K)
 
Signature:  $[0, 21]$
sage: K.signature()
 
gp: K.sign
 
magma: Signature(K);
 
oscar: signature(K)
 
Discriminant:   \(-74252462132603256348231837398371002884673933378885582779211491265789772693504\) \(\medspace = -\,2^{42}\cdot 7^{76}\) 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:  \(67.65\)
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:  $2\cdot 7^{38/21}\approx 67.6480092151321$
Ramified primes:   \(2\), \(7\) 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:  \(\Q(\sqrt{-1}) \)
$\card{ \Gal(K/\Q) }$:  $42$
sage: K.automorphisms()
 
magma: Automorphisms(K);
 
oscar: automorphisms(K)
 
This field is Galois and abelian over $\Q$.
Conductor:  \(196=2^{2}\cdot 7^{2}\)
Dirichlet character group:    $\lbrace$$\chi_{196}(1,·)$, $\chi_{196}(51,·)$, $\chi_{196}(135,·)$, $\chi_{196}(9,·)$, $\chi_{196}(11,·)$, $\chi_{196}(141,·)$, $\chi_{196}(15,·)$, $\chi_{196}(149,·)$, $\chi_{196}(23,·)$, $\chi_{196}(25,·)$, $\chi_{196}(155,·)$, $\chi_{196}(29,·)$, $\chi_{196}(163,·)$, $\chi_{196}(37,·)$, $\chi_{196}(65,·)$, $\chi_{196}(39,·)$, $\chi_{196}(169,·)$, $\chi_{196}(43,·)$, $\chi_{196}(177,·)$, $\chi_{196}(179,·)$, $\chi_{196}(53,·)$, $\chi_{196}(137,·)$, $\chi_{196}(57,·)$, $\chi_{196}(151,·)$, $\chi_{196}(191,·)$, $\chi_{196}(193,·)$, $\chi_{196}(67,·)$, $\chi_{196}(71,·)$, $\chi_{196}(183,·)$, $\chi_{196}(79,·)$, $\chi_{196}(81,·)$, $\chi_{196}(85,·)$, $\chi_{196}(93,·)$, $\chi_{196}(95,·)$, $\chi_{196}(165,·)$, $\chi_{196}(99,·)$, $\chi_{196}(107,·)$, $\chi_{196}(109,·)$, $\chi_{196}(113,·)$, $\chi_{196}(121,·)$, $\chi_{196}(123,·)$, $\chi_{196}(127,·)$$\rbrace$
This is a CM field.
Reflex fields:  unavailable$^{1048576}$

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

$1$, $a$, $a^{2}$, $a^{3}$, $a^{4}$, $a^{5}$, $a^{6}$, $a^{7}$, $a^{8}$, $a^{9}$, $a^{10}$, $a^{11}$, $a^{12}$, $a^{13}$, $a^{14}$, $a^{15}$, $a^{16}$, $a^{17}$, $a^{18}$, $a^{19}$, $a^{20}$, $a^{21}$, $a^{22}$, $a^{23}$, $a^{24}$, $a^{25}$, $a^{26}$, $a^{27}$, $a^{28}$, $a^{29}$, $a^{30}$, $a^{31}$, $a^{32}$, $a^{33}$, $a^{34}$, $a^{35}$, $a^{36}$, $a^{37}$, $a^{38}$, $a^{39}$, $a^{40}$, $a^{41}$ Copy content Toggle raw display

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

Monogenic:  Yes
Index:  $1$
Inessential primes:  None

Class group and class number

$C_{1923461}$, which has order $1923461$ (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:  $20$
sage: UK.rank()
 
gp: K.fu
 
magma: UnitRank(K);
 
oscar: rank(UK)
 
Torsion generator:   \( a^{35} + 35 a^{33} + 560 a^{31} + 5425 a^{29} + 35525 a^{27} + 166257 a^{25} + 573300 a^{23} + 1480049 a^{21} + 2877854 a^{19} + 4205936 a^{17} + 4575312 a^{15} + 3637270 a^{13} + 2051777 a^{11} + 784343 a^{9} + 188653 a^{7} + 25060 a^{5} + 1414 a^{3} + 21 a \)  (order $4$) 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:   $a^{14}+14a^{12}+77a^{10}+210a^{8}+294a^{6}+196a^{4}+49a^{2}+1$, $a^{35}+35a^{33}+560a^{31}+5425a^{29}+35525a^{27}+166257a^{25}+573300a^{23}+1480049a^{21}+2877854a^{19}+4205936a^{17}+4575312a^{15}+3637270a^{13}+2051777a^{11}+784343a^{9}+188652a^{7}+25053a^{5}+1400a^{3}+14a$, $a^{11}+11a^{9}+44a^{7}+77a^{5}+55a^{3}+11a$, $a^{10}+10a^{8}+35a^{6}+50a^{4}+25a^{2}+2$, $a^{5}+5a^{3}+5a$, $a^{27}+27a^{25}+324a^{23}+2277a^{21}+10395a^{19}+32319a^{17}+69768a^{15}+104652a^{13}+107406a^{11}+72930a^{9}+30888a^{7}+7371a^{5}+819a^{3}+27a$, $a^{30}+30a^{28}+405a^{26}+3250a^{24}+17250a^{22}+63756a^{20}+168245a^{18}+319770a^{16}+436050a^{14}+419900a^{12}+277134a^{10}+119340a^{8}+30940a^{6}+4200a^{4}+225a^{2}+2$, $a^{34}+34a^{32}+527a^{30}+4930a^{28}+31059a^{26}+139230a^{24}+457470a^{22}+1118260a^{20}+2042975a^{18}+2778446a^{16}+2778446a^{14}+1998724a^{12}+999362a^{10}+329460a^{8}+65892a^{6}+6936a^{4}+289a^{2}+2$, $a^{17}+17a^{15}+119a^{13}+442a^{11}+935a^{9}+1122a^{7}+714a^{5}+204a^{3}+17a$, $a^{33}+33a^{31}+495a^{29}+4466a^{27}+27027a^{25}+115830a^{23}+361790a^{21}+834900a^{19}+1427679a^{17}+1797818a^{15}+1641486a^{13}+1058148a^{11}+461890a^{9}+127908a^{7}+20196a^{5}+1496a^{3}+33a$, $a^{8}+8a^{6}+20a^{4}+16a^{2}+2$, $a^{4}+4a^{2}+2$, $a^{24}+24a^{22}+252a^{20}+1520a^{18}+5814a^{16}+14688a^{14}+24752a^{12}+27456a^{10}+19305a^{8}+8008a^{6}+1716a^{4}+144a^{2}+2$, $a^{31}+31a^{29}+434a^{27}+3627a^{25}+20150a^{23}+78430a^{21}+219604a^{19}+447051a^{17}+660858a^{15}+700910a^{13}+520676a^{11}+260338a^{9}+82212a^{7}+14756a^{5}+1240a^{3}+31a$, $a^{36}+35a^{34}+560a^{32}+5425a^{30}+35525a^{28}+166257a^{26}+573300a^{24}+1480049a^{22}+2877854a^{20}+4205936a^{18}+4575312a^{16}+3637270a^{14}+2051777a^{12}+784343a^{10}+188653a^{8}+25060a^{6}+1414a^{4}+21a^{2}$, $a^{35}+35a^{33}+560a^{31}+5425a^{29}+35525a^{27}+166258a^{25}+573325a^{23}+1480324a^{21}+2879604a^{19}+4213061a^{17}+4594692a^{15}+3672970a^{13}+2095977a^{11}+820093a^{9}+206528a^{7}+30065a^{5}+2064a^{3}+47a$, $a^{40}+40a^{38}+740a^{36}+8400a^{34}+65450a^{32}+371008a^{30}+1582240a^{28}+5178240a^{26}+13147875a^{24}+26013000a^{22}+40060020a^{20}+47720400a^{18}+43459650a^{16}+29716000a^{14}+14858000a^{12}+5230016a^{10}+1225785a^{8}+175560a^{6}+13300a^{4}+400a^{2}+2$, $a^{20}+20a^{18}+170a^{16}+800a^{14}+2275a^{12}+4004a^{10}+4290a^{8}+2640a^{6}+825a^{4}+100a^{2}+2$, $a^{6}+6a^{4}+9a^{2}+2$, $a^{2}+2$ 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:  \( 1776855897760068.5 \) (assuming GRH)
sage: K.regulator()
 
gp: K.reg
 
magma: Regulator(K);
 
oscar: regulator(K)
 

Class number formula

\[ \begin{aligned}\lim_{s\to 1} (s-1)\zeta_K(s) =\mathstrut & \frac{2^{r_1}\cdot (2\pi)^{r_2}\cdot R\cdot h}{w\cdot\sqrt{|D|}}\cr \approx\mathstrut &\frac{2^{0}\cdot(2\pi)^{21}\cdot 1776855897760068.5 \cdot 1923461}{4\cdot\sqrt{74252462132603256348231837398371002884673933378885582779211491265789772693504}}\cr\approx \mathstrut & 0.181174640338776 \end{aligned}\] (assuming GRH)

# self-contained SageMath code snippet to compute the analytic class number formula
 
x = polygen(QQ); K.<a> = NumberField(x^42 + 42*x^40 + 819*x^38 + 9842*x^36 + 81585*x^34 + 494802*x^32 + 2272424*x^30 + 8069423*x^28 + 22428224*x^26 + 49085050*x^24 + 84669739*x^22 + 114704933*x^20 + 121049551*x^18 + 98190708*x^16 + 60019861*x^14 + 26865216*x^12 + 8444436*x^10 + 1749188*x^8 + 215453*x^6 + 13181*x^4 + 294*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^42 + 42*x^40 + 819*x^38 + 9842*x^36 + 81585*x^34 + 494802*x^32 + 2272424*x^30 + 8069423*x^28 + 22428224*x^26 + 49085050*x^24 + 84669739*x^22 + 114704933*x^20 + 121049551*x^18 + 98190708*x^16 + 60019861*x^14 + 26865216*x^12 + 8444436*x^10 + 1749188*x^8 + 215453*x^6 + 13181*x^4 + 294*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^42 + 42*x^40 + 819*x^38 + 9842*x^36 + 81585*x^34 + 494802*x^32 + 2272424*x^30 + 8069423*x^28 + 22428224*x^26 + 49085050*x^24 + 84669739*x^22 + 114704933*x^20 + 121049551*x^18 + 98190708*x^16 + 60019861*x^14 + 26865216*x^12 + 8444436*x^10 + 1749188*x^8 + 215453*x^6 + 13181*x^4 + 294*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^42 + 42*x^40 + 819*x^38 + 9842*x^36 + 81585*x^34 + 494802*x^32 + 2272424*x^30 + 8069423*x^28 + 22428224*x^26 + 49085050*x^24 + 84669739*x^22 + 114704933*x^20 + 121049551*x^18 + 98190708*x^16 + 60019861*x^14 + 26865216*x^12 + 8444436*x^10 + 1749188*x^8 + 215453*x^6 + 13181*x^4 + 294*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

$C_{42}$ (as 42T1):

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 cyclic group of order 42
The 42 conjugacy class representatives for $C_{42}$
Character table for $C_{42}$ is not computed

Intermediate fields

\(\Q(\sqrt{-1}) \), \(\Q(\zeta_{7})^+\), 6.0.153664.1, 7.7.13841287201.1, 14.0.3138866894939200133545984.1, \(\Q(\zeta_{49})^+\)

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]
 

Frobenius cycle types

$p$ $2$ $3$ $5$ $7$ $11$ $13$ $17$ $19$ $23$ $29$ $31$ $37$ $41$ $43$ $47$ $53$ $59$
Cycle type R $42$ $21^{2}$ R $42$ ${\href{/padicField/13.7.0.1}{7} }^{6}$ $21^{2}$ ${\href{/padicField/19.6.0.1}{6} }^{7}$ $42$ ${\href{/padicField/29.7.0.1}{7} }^{6}$ ${\href{/padicField/31.6.0.1}{6} }^{7}$ $21^{2}$ ${\href{/padicField/41.7.0.1}{7} }^{6}$ ${\href{/padicField/43.14.0.1}{14} }^{3}$ $42$ $21^{2}$ $42$

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 Deg $42$$2$$21$$42$
\(7\) Copy content Toggle raw display Deg $42$$21$$2$$76$