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Properties

Label 18T38
Degree $18$
Order $72$
Cyclic no
Abelian no
Solvable yes
Primitive no
$p$-group no
Group: $C_2^2:D_9$

Related objects

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Group action invariants

Degree $n$:  $18$
Transitive number $t$:  $38$
Group:  $C_2^2:D_9$
Parity:  $1$
Primitive:  no
Nilpotency class:  $-1$ (not nilpotent)
$|\Aut(F/K)|$:  $2$
Generators:  (1,15)(2,16)(3,14)(4,13)(5,18)(6,17)(9,12)(10,11), (1,8,2,7)(3,12,4,11)(5,9,6,10)(13,14)(15,18)(16,17)

Low degree resolvents

|G/N|Galois groups for stem field(s)
$2$:  $C_2$
$6$:  $S_3$
$18$:  $D_{9}$
$24$:  $S_4$

Resolvents shown for degrees $\leq 47$

Subfields

Degree 2: None

Degree 3: $S_3$

Degree 6: $S_4$

Degree 9: $D_{9}$

Low degree siblings

18T39

Siblings are shown with degree $\leq 47$

A number field with this Galois group has no arithmetically equivalent fields.

Conjugacy classes

Cycle TypeSizeOrderRepresentative
$ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 $ $1$ $1$ $()$
$ 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1 $ $3$ $2$ $( 7, 8)( 9,10)(11,12)(13,14)(15,16)(17,18)$
$ 2, 2, 2, 2, 2, 2, 2, 2, 1, 1 $ $18$ $2$ $( 3, 5)( 4, 6)( 7,17)( 8,18)( 9,15)(10,16)(11,14)(12,13)$
$ 4, 4, 4, 2, 2, 2 $ $18$ $4$ $( 1, 2)( 3, 6)( 4, 5)( 7,17, 8,18)( 9,15,10,16)(11,14,12,13)$
$ 6, 6, 3, 3 $ $6$ $6$ $( 1, 3, 6, 2, 4, 5)( 7, 9,12)( 8,10,11)(13,16,17,14,15,18)$
$ 3, 3, 3, 3, 3, 3 $ $2$ $3$ $( 1, 4, 6)( 2, 3, 5)( 7, 9,12)( 8,10,11)(13,15,17)(14,16,18)$
$ 9, 9 $ $8$ $9$ $( 1, 7,15, 6,12,13, 4, 9,17)( 2, 8,16, 5,11,14, 3,10,18)$
$ 9, 9 $ $8$ $9$ $( 1, 9,13, 6, 7,17, 4,12,15)( 2,10,14, 5, 8,18, 3,11,16)$
$ 9, 9 $ $8$ $9$ $( 1,11,18, 6,10,16, 4, 8,14)( 2,12,17, 5, 9,15, 3, 7,13)$

Group invariants

Order:  $72=2^{3} \cdot 3^{2}$
Cyclic:  no
Abelian:  no
Solvable:  yes
GAP id:  [72, 15]
Character table:    
     2  3  3  2  2  2  2  .  .  .
     3  2  1  .  .  1  2  2  2  2

       1a 2a 2b 4a 6a 3a 9a 9b 9c
    2P 1a 1a 1a 2a 3a 3a 9b 9c 9a
    3P 1a 2a 2b 4a 2a 1a 3a 3a 3a
    5P 1a 2a 2b 4a 6a 3a 9c 9a 9b
    7P 1a 2a 2b 4a 6a 3a 9b 9c 9a

X.1     1  1  1  1  1  1  1  1  1
X.2     1  1 -1 -1  1  1  1  1  1
X.3     2  2  .  .  2  2 -1 -1 -1
X.4     2  2  .  . -1 -1  A  C  B
X.5     2  2  .  . -1 -1  B  A  C
X.6     2  2  .  . -1 -1  C  B  A
X.7     3 -1 -1  1 -1  3  .  .  .
X.8     3 -1  1 -1 -1  3  .  .  .
X.9     6 -2  .  .  1 -3  .  .  .

A = E(9)^4+E(9)^5
B = E(9)^2+E(9)^7
C = -E(9)^2-E(9)^4-E(9)^5-E(9)^7