Properties

Label 320.1508.4.k1
Order $ 2^{4} \cdot 5 $
Index $ 2^{2} $
Normal Yes

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Subgroup ($H$) information

Description:$Q_8:D_5$
Order: \(80\)\(\medspace = 2^{4} \cdot 5 \)
Index: \(4\)\(\medspace = 2^{2} \)
Exponent: \(40\)\(\medspace = 2^{3} \cdot 5 \)
Generators: $a, c^{2}, c^{4}, c, d^{2}$ Copy content Toggle raw display
Derived length: $2$

The subgroup is characteristic (hence normal), a semidirect factor, nonabelian, supersolvable (hence solvable and monomial), hyperelementary for $p = 2$, and metabelian.

Ambient group ($G$) information

Description: $C_{20}.C_2^4$
Order: \(320\)\(\medspace = 2^{6} \cdot 5 \)
Exponent: \(40\)\(\medspace = 2^{3} \cdot 5 \)
Derived length:$2$

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

Quotient group ($Q$) structure

Description: $C_2^2$
Order: \(4\)\(\medspace = 2^{2} \)
Exponent: \(2\)
Automorphism Group: $S_3$, of order \(6\)\(\medspace = 2 \cdot 3 \)
Outer Automorphisms: $S_3$, of order \(6\)\(\medspace = 2 \cdot 3 \)
Derived length: $1$

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

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)$$D_{10}.(C_2^4\times S_4)$, of order \(7680\)\(\medspace = 2^{9} \cdot 3 \cdot 5 \)
$\operatorname{Aut}(H)$ $D_{10}.C_2^4$, of order \(320\)\(\medspace = 2^{6} \cdot 5 \)
$\operatorname{res}(\operatorname{Aut}(G))$$D_{10}.C_2^4$, of order \(320\)\(\medspace = 2^{6} \cdot 5 \)
$\card{\operatorname{ker}(\operatorname{res})}$\(24\)\(\medspace = 2^{3} \cdot 3 \)
$W$$C_5:D_4$, of order \(40\)\(\medspace = 2^{3} \cdot 5 \)

Related subgroups

Centralizer:$Q_8$
Normalizer:$C_{20}.C_2^4$
Complements:$C_2^2$
Minimal over-subgroups:$C_{20}.D_4$
Maximal under-subgroups:$D_{20}$$C_5\times Q_8$$C_5:C_8$$\SD_{16}$

Other information

Number of conjugacy classes in this autjugacy class$1$
Möbius function$2$
Projective image$C_2^3:D_{10}$