Properties

Label 81.5.3.a1.a1
Order $ 3^{3} $
Index $ 3 $
Normal Yes

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Subgroup ($H$) information

Description:$C_3\times C_9$
Order: \(27\)\(\medspace = 3^{3} \)
Index: \(3\)
Exponent: \(9\)\(\medspace = 3^{2} \)
Generators: $a, b^{3}$ Copy content Toggle raw display
Nilpotency class: $1$
Derived length: $1$

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

Ambient group ($G$) information

Description: $C_3\times C_{27}$
Order: \(81\)\(\medspace = 3^{4} \)
Exponent: \(27\)\(\medspace = 3^{3} \)
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: $C_3$
Order: \(3\)
Exponent: \(3\)
Automorphism Group: $C_2$, of order \(2\)
Outer Automorphisms: $C_2$, of order \(2\)
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), a $p$-group, and simple.

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)$$(C_3\times C_{18}):S_3$, of order \(324\)\(\medspace = 2^{2} \cdot 3^{4} \)
$\operatorname{Aut}(H)$ $C_3^2:D_6$, of order \(108\)\(\medspace = 2^{2} \cdot 3^{3} \)
$\operatorname{res}(\operatorname{Aut}(G))$$C_6\times S_3$, of order \(36\)\(\medspace = 2^{2} \cdot 3^{2} \)
$\card{\operatorname{ker}(\operatorname{res})}$\(9\)\(\medspace = 3^{2} \)
$W$$C_1$, of order $1$

Related subgroups

Centralizer:$C_3\times C_{27}$
Normalizer:$C_3\times C_{27}$
Minimal over-subgroups:$C_3\times C_{27}$
Maximal under-subgroups:$C_3^2$$C_9$$C_9$$C_9$

Other information

Möbius function$-1$
Projective image$C_3$