Properties

Label 128.2216.8.r1
Order $ 2^{4} $
Index $ 2^{3} $
Normal Yes

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Subgroup ($H$) information

Description:$C_2\times D_4$
Order: \(16\)\(\medspace = 2^{4} \)
Index: \(8\)\(\medspace = 2^{3} \)
Exponent: \(4\)\(\medspace = 2^{2} \)
Generators: $\langle(1,5)(2,3)(4,8)(6,7)(9,11), (1,6)(2,7)(3,8)(4,5)(9,10)(11,12), (1,3)(2,5)(4,7)(6,8), (9,11)(10,12)\rangle$ Copy content Toggle raw display
Nilpotency class: $2$
Derived length: $2$

The subgroup is normal, a semidirect factor, nonabelian, a $p$-group (hence nilpotent, solvable, supersolvable, monomial, elementary, and hyperelementary), metabelian, and rational.

Ambient group ($G$) information

Description: $D_4^2:C_2$
Order: \(128\)\(\medspace = 2^{7} \)
Exponent: \(4\)\(\medspace = 2^{2} \)
Nilpotency class:$2$
Derived length:$2$

The ambient group is nonabelian, a $p$-group (hence nilpotent, solvable, supersolvable, monomial, elementary, and hyperelementary), metabelian, and rational.

Quotient group ($Q$) structure

Description: $C_2^3$
Order: \(8\)\(\medspace = 2^{3} \)
Exponent: \(2\)
Automorphism Group: $\PSL(2,7)$, of order \(168\)\(\medspace = 2^{3} \cdot 3 \cdot 7 \)
Outer Automorphisms: $\PSL(2,7)$, of order \(168\)\(\medspace = 2^{3} \cdot 3 \cdot 7 \)
Nilpotency class: $1$
Derived length: $1$

The quotient is abelian (hence nilpotent, solvable, supersolvable, monomial, metabelian, and an A-group), a $p$-group (hence elementary and hyperelementary), and rational.

Automorphism information

While the subgroup $H$ is not characteristic, the stabilizer $S$ of $H$ in the automorphism group $\operatorname{Aut}(G)$ of the ambient group acts on $H$, yielding a homomorphism $\operatorname{res} : S \to \operatorname{Aut}(H)$. The image of $\operatorname{res}$ on the inner automorphisms $\operatorname{Inn}(G) \cap S$ is the Weyl group $W = N_G(H) / Z_G(H)$.

$\operatorname{Aut}(G)$$C_2^8.D_4^2$, of order \(16384\)\(\medspace = 2^{14} \)
$\operatorname{Aut}(H)$ $C_2\wr C_2^2$, of order \(64\)\(\medspace = 2^{6} \)
$\operatorname{res}(S)$$C_2^4$, of order \(16\)\(\medspace = 2^{4} \)
$\card{\operatorname{ker}(\operatorname{res})}$\(64\)\(\medspace = 2^{6} \)
$W$$C_2^4$, of order \(16\)\(\medspace = 2^{4} \)

Related subgroups

Centralizer:$C_2^3$
Normalizer:$D_4^2:C_2$
Complements:$C_2^3$
Minimal over-subgroups:$C_2^2\wr C_2$$C_2^2\times D_4$$C_4:D_4$$C_2^2\wr C_2$$C_2^2\wr C_2$$C_4:D_4$$C_4:D_4$
Maximal under-subgroups:$C_2^3$$C_2^3$$C_2\times C_4$$D_4$

Other information

Number of subgroups in this autjugacy class$16$
Number of conjugacy classes in this autjugacy class$16$
Möbius function$-8$
Projective image$C_2^5$