Properties

Label 16.5.8.a1.a1
Order $ 2 $
Index $ 2^{3} $
Normal Yes

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Subgroup ($H$) information

Description:$C_2$
Order: \(2\)
Index: \(8\)\(\medspace = 2^{3} \)
Exponent: \(2\)
Generators: $a$ Copy content Toggle raw display
Nilpotency class: $1$
Derived length: $1$

The subgroup is normal, a direct factor, cyclic (hence abelian, nilpotent, solvable, supersolvable, monomial, elementary, hyperelementary, metacyclic, metabelian, a Z-group, and an A-group), central, a $p$-group, simple, and rational.

Ambient group ($G$) information

Description: $C_2\times C_8$
Order: \(16\)\(\medspace = 2^{4} \)
Exponent: \(8\)\(\medspace = 2^{3} \)
Nilpotency class:$1$
Derived length:$1$

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

Quotient group ($Q$) structure

Description: $C_8$
Order: \(8\)\(\medspace = 2^{3} \)
Exponent: \(8\)\(\medspace = 2^{3} \)
Automorphism Group: $C_2^2$, of order \(4\)\(\medspace = 2^{2} \)
Outer Automorphisms: $C_2^2$, of order \(4\)\(\medspace = 2^{2} \)
Nilpotency class: $1$
Derived length: $1$

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

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\times D_4$, of order \(16\)\(\medspace = 2^{4} \)
$\operatorname{Aut}(H)$ $C_1$, of order $1$
$\operatorname{res}(S)$$C_1$, of order $1$
$\card{\operatorname{ker}(\operatorname{res})}$\(8\)\(\medspace = 2^{3} \)
$W$$C_1$, of order $1$

Related subgroups

Centralizer:$C_2\times C_8$
Normalizer:$C_2\times C_8$
Complements:$C_8$ $C_8$
Minimal over-subgroups:$C_2^2$
Maximal under-subgroups:$C_1$
Autjugate subgroups:16.5.8.a1.b1

Other information

Möbius function$0$
Projective image$C_8$