Properties

Label 840.110.5.a1.a1
Order $ 2^{3} \cdot 3 \cdot 7 $
Index $ 5 $
Normal No

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Subgroup ($H$) information

Description:$C_{21}:D_4$
Order: \(168\)\(\medspace = 2^{3} \cdot 3 \cdot 7 \)
Index: \(5\)
Exponent: \(84\)\(\medspace = 2^{2} \cdot 3 \cdot 7 \)
Generators: $\left(\begin{array}{rr} 0 & 1 \\ 1 & 0 \end{array}\right), \left(\begin{array}{rr} 43 & 0 \\ 0 & 34 \end{array}\right), \left(\begin{array}{rr} 12 & 0 \\ 0 & 88 \end{array}\right), \left(\begin{array}{rr} 144 & 0 \\ 0 & 148 \end{array}\right), \left(\begin{array}{rr} 1 & 0 \\ 0 & 210 \end{array}\right)$ Copy content Toggle raw display
Derived length: $2$

The subgroup is maximal, nonabelian, a Hall subgroup, supersolvable (hence solvable and monomial), hyperelementary for $p = 2$, and metabelian.

Ambient group ($G$) information

Description: $C_{105}:D_4$
Order: \(840\)\(\medspace = 2^{3} \cdot 3 \cdot 5 \cdot 7 \)
Exponent: \(420\)\(\medspace = 2^{2} \cdot 3 \cdot 5 \cdot 7 \)
Derived length:$2$

The ambient group is nonabelian, supersolvable (hence solvable and monomial), hyperelementary for $p = 2$, and metabelian.

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_2^2\times C_7:(C_2\times C_6\times F_5)$
$\operatorname{Aut}(H)$ $C_2^3\times F_7$, of order \(336\)\(\medspace = 2^{4} \cdot 3 \cdot 7 \)
$\operatorname{res}(S)$$C_2^3\times F_7$, of order \(336\)\(\medspace = 2^{4} \cdot 3 \cdot 7 \)
$\card{\operatorname{ker}(\operatorname{res})}$\(4\)\(\medspace = 2^{2} \)
$W$$D_{14}$, of order \(28\)\(\medspace = 2^{2} \cdot 7 \)

Related subgroups

Centralizer:$C_6$
Normalizer:$C_{21}:D_4$
Normal closure:$C_{105}:D_4$
Core:$C_2\times C_{42}$
Minimal over-subgroups:$C_{105}:D_4$
Maximal under-subgroups:$C_2\times C_{42}$$C_3\times D_{14}$$C_7:C_{12}$$C_7:D_4$$C_3\times D_4$

Other information

Number of subgroups in this conjugacy class$5$
Möbius function$-1$
Projective image$D_{70}$