Properties

Label 168.49.42.a1.a1
Order $ 2^{2} $
Index $ 2 \cdot 3 \cdot 7 $
Normal Yes

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Subgroup ($H$) information

Description:$C_2^2$
Order: \(4\)\(\medspace = 2^{2} \)
Index: \(42\)\(\medspace = 2 \cdot 3 \cdot 7 \)
Exponent: \(2\)
Generators: $b, c^{7}$ Copy content Toggle raw display
Nilpotency class: $1$
Derived length: $1$

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

Ambient group ($G$) information

Description: $D_7:A_4$
Order: \(168\)\(\medspace = 2^{3} \cdot 3 \cdot 7 \)
Exponent: \(42\)\(\medspace = 2 \cdot 3 \cdot 7 \)
Derived length:$2$

The ambient group is nonabelian, monomial (hence solvable), metabelian, and an A-group.

Quotient group ($Q$) structure

Description: $F_7$
Order: \(42\)\(\medspace = 2 \cdot 3 \cdot 7 \)
Exponent: \(42\)\(\medspace = 2 \cdot 3 \cdot 7 \)
Automorphism Group: $F_7$, of order \(42\)\(\medspace = 2 \cdot 3 \cdot 7 \)
Outer Automorphisms: $C_1$, of order $1$
Nilpotency class: $-1$
Derived length: $2$

The quotient is nonabelian and a Z-group (hence solvable, supersolvable, monomial, metacyclic, metabelian, and an A-group).

Automorphism information

Since the subgroup $H$ is characteristic, the automorphism group $\operatorname{Aut}(G)$ of the ambient group acts on $H$, yielding a homomorphism $\operatorname{res} : \operatorname{Aut}(G) \to \operatorname{Aut}(H)$. The image of $\operatorname{res}$ on the inner automorphism group $\operatorname{Inn}(G)$ is the Weyl group $W = G / Z_G(H)$.

$\operatorname{Aut}(G)$$A_4\times F_7$, of order \(504\)\(\medspace = 2^{3} \cdot 3^{2} \cdot 7 \)
$\operatorname{Aut}(H)$ $S_3$, of order \(6\)\(\medspace = 2 \cdot 3 \)
$\operatorname{res}(\operatorname{Aut}(G))$$C_3$, of order \(3\)
$\card{\operatorname{ker}(\operatorname{res})}$\(168\)\(\medspace = 2^{3} \cdot 3 \cdot 7 \)
$W$$C_3$, of order \(3\)

Related subgroups

Centralizer:$C_2\times D_{14}$
Normalizer:$D_7:A_4$
Complements:$F_7$
Minimal over-subgroups:$C_2\times C_{14}$$A_4$$C_2^3$
Maximal under-subgroups:$C_2$

Other information

Möbius function$-7$
Projective image$D_7:A_4$