Properties

Label 8T2
8T2 1 2 1->2 5 1->5 3 2->3 6 2->6 7 3->7 8 3->8 4 4->5 4->8 5->6 6->7 7->4 8->1
Degree $8$
Order $8$
Cyclic no
Abelian yes
Solvable yes
Primitive no
$p$-group yes
Group: $C_4\times C_2$

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Copy content magma:G := TransitiveGroup(8, 2);
 

Group invariants

Abstract group:  $C_4\times C_2$
Copy content magma:IdentifyGroup(G);
 
Order:  $8=2^{3}$
Copy content magma:Order(G);
 
Cyclic:  no
Copy content magma:IsCyclic(G);
 
Abelian:  yes
Copy content magma:IsAbelian(G);
 
Solvable:  yes
Copy content magma:IsSolvable(G);
 
Nilpotency class:  $1$
Copy content magma:NilpotencyClass(G);
 

Group action invariants

Degree $n$:  $8$
Copy content magma:t, n := TransitiveGroupIdentification(G); n;
 
Transitive number $t$:  $2$
Copy content magma:t, n := TransitiveGroupIdentification(G); t;
 
CHM label:   $4[x]2$
Parity:  $1$
Copy content magma:IsEven(G);
 
Primitive:  no
Copy content magma:IsPrimitive(G);
 
$\card{\Aut(F/K)}$:  $8$
Copy content magma:Order(Centralizer(SymmetricGroup(n), G));
 
Generators:  $(1,2,3,8)(4,5,6,7)$, $(1,5)(2,6)(3,7)(4,8)$
Copy content magma:Generators(G);
 

Low degree resolvents

$\card{(G/N)}$Galois groups for stem field(s)
$2$:  $C_2$ x 3
$4$:  $C_4$ x 2, $C_2^2$

Resolvents shown for degrees $\leq 47$

Subfields

Degree 2: $C_2$ x 3

Degree 4: $C_4$ x 2, $C_2^2$

Low degree siblings

There are no siblings with degree $\leq 47$
A number field with this Galois group has no arithmetically equivalent fields.

Conjugacy classes

LabelCycle TypeSizeOrderIndexRepresentative
1A $1^{8}$ $1$ $1$ $0$ $()$
2A $2^{4}$ $1$ $2$ $4$ $(1,5)(2,6)(3,7)(4,8)$
2B $2^{4}$ $1$ $2$ $4$ $(1,7)(2,4)(3,5)(6,8)$
2C $2^{4}$ $1$ $2$ $4$ $(1,3)(2,8)(4,6)(5,7)$
4A1 $4^{2}$ $1$ $4$ $6$ $(1,2,3,8)(4,5,6,7)$
4A-1 $4^{2}$ $1$ $4$ $6$ $(1,8,3,2)(4,7,6,5)$
4B1 $4^{2}$ $1$ $4$ $6$ $(1,6,3,4)(2,7,8,5)$
4B-1 $4^{2}$ $1$ $4$ $6$ $(1,4,3,6)(2,5,8,7)$

Malle's constant $a(G)$:     $1/4$

Copy content magma:ConjugacyClasses(G);
 

Character table

1A 2A 2B 2C 4A1 4A-1 4B1 4B-1
Size 1 1 1 1 1 1 1 1
2 P 1A 1A 1A 1A 2C 2C 2C 2C
Type
8.2.1a R 1 1 1 1 1 1 1 1
8.2.1b R 1 1 1 1 1 1 1 1
8.2.1c R 1 1 1 1 1 1 1 1
8.2.1d R 1 1 1 1 1 1 1 1
8.2.1e1 C 1 1 1 1 i i i i
8.2.1e2 C 1 1 1 1 i i i i
8.2.1f1 C 1 1 1 1 i i i i
8.2.1f2 C 1 1 1 1 i i i i

Copy content magma:CharacterTable(G);
 

Regular extensions

$f_{ 1 } =$ $t^{2} x^{8} + \left(2 t^{3} + 16 t\right) x^{6} + \left(t^{4} + 14 t^{2} + 64\right) x^{4} + \left(2 t^{3} + 48 t\right) x^{2} + t^{2}$ Copy content Toggle raw display