Properties

Label 8T9
8T9 1 3 1->3 5 1->5 8 1->8 2 2->3 6 2->6 2->8 7 3->7 4 4->5 4->5 4->6 4->8 5->7 6->7 6->7
Degree $8$
Order $16$
Cyclic no
Abelian no
Solvable yes
Primitive no
$p$-group yes
Group: $D_4\times C_2$

Related objects

Downloads

Learn more

Show commands: Magma

Copy content magma:G := TransitiveGroup(8, 9);
 

Group invariants

Abstract group:  $D_4\times C_2$
Copy content magma:IdentifyGroup(G);
 
Order:  $16=2^{4}$
Copy content magma:Order(G);
 
Cyclic:  no
Copy content magma:IsCyclic(G);
 
Abelian:  no
Copy content magma:IsAbelian(G);
 
Solvable:  yes
Copy content magma:IsSolvable(G);
 
Nilpotency class:  $2$
Copy content magma:NilpotencyClass(G);
 

Group action invariants

Degree $n$:  $8$
Copy content magma:t, n := TransitiveGroupIdentification(G); n;
 
Transitive number $t$:  $9$
Copy content magma:t, n := TransitiveGroupIdentification(G); t;
 
CHM label:   $E(8):2=D(4)[x]2$
Parity:  $1$
Copy content magma:IsEven(G);
 
Primitive:  no
Copy content magma:IsPrimitive(G);
 
$\card{\Aut(F/K)}$:  $4$
Copy content magma:Order(Centralizer(SymmetricGroup(n), G));
 
Generators:  $(1,3)(2,8)(4,6)(5,7)$, $(4,5)(6,7)$, $(1,8)(2,3)(4,5)(6,7)$, $(1,5)(2,6)(3,7)(4,8)$
Copy content magma:Generators(G);
 

Low degree resolvents

$\card{(G/N)}$Galois groups for stem field(s)
$2$:  $C_2$ x 7
$4$:  $C_2^2$ x 7
$8$:  $D_{4}$ x 2, $C_2^3$

Resolvents shown for degrees $\leq 47$

Subfields

Degree 2: $C_2$ x 3

Degree 4: $C_2^2$, $D_{4}$ x 2

Low degree siblings

8T9 x 3, 16T9

Siblings are shown 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 $2^{4}$ $1$ $2$ $4$ $(1,3)(2,8)(4,6)(5,7)$
2B $2^{4}$ $1$ $2$ $4$ $(1,2)(3,8)(4,7)(5,6)$
2C $2^{4}$ $1$ $2$ $4$ $(1,8)(2,3)(4,5)(6,7)$
2D $2^{2},1^{4}$ $2$ $2$ $2$ $(4,5)(6,7)$
2E $2^{4}$ $2$ $2$ $4$ $(1,3)(2,8)(4,7)(5,6)$
2F $2^{4}$ $2$ $2$ $4$ $(1,5)(2,6)(3,7)(4,8)$
2G $2^{4}$ $2$ $2$ $4$ $(1,7)(2,4)(3,5)(6,8)$
4A $4^{2}$ $2$ $4$ $6$ $(1,5,8,4)(2,6,3,7)$
4B $4^{2}$ $2$ $4$ $6$ $(1,7,8,6)(2,4,3,5)$

Malle's constant $a(G)$:     $1/2$

Copy content magma:ConjugacyClasses(G);
 

Character table

1A 2A 2B 2C 2D 2E 2F 2G 4A 4B
Size 1 1 1 1 2 2 2 2 2 2
2 P 1A 1A 1A 1A 1A 1A 1A 1A 2C 2C
Type
16.11.1a R 1 1 1 1 1 1 1 1 1 1
16.11.1b R 1 1 1 1 1 1 1 1 1 1
16.11.1c R 1 1 1 1 1 1 1 1 1 1
16.11.1d R 1 1 1 1 1 1 1 1 1 1
16.11.1e R 1 1 1 1 1 1 1 1 1 1
16.11.1f R 1 1 1 1 1 1 1 1 1 1
16.11.1g R 1 1 1 1 1 1 1 1 1 1
16.11.1h R 1 1 1 1 1 1 1 1 1 1
16.11.2a R 2 2 2 2 0 0 0 0 0 0
16.11.2b R 2 2 2 2 0 0 0 0 0 0

Copy content magma:CharacterTable(G);
 

Regular extensions

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