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Properties

Label 7T3
Order \(21\)
n \(7\)
Cyclic No
Abelian No
Solvable Yes
Primitive Yes
$p$-group No
Group: $C_7:C_3$

Related objects

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Group action invariants

Degree $n$ :  $7$
Transitive number $t$ :  $3$
Group :  $C_7:C_3$
CHM label :  $F_{21}(7) = 7:3$
Parity:  $1$
Primitive:  Yes
Nilpotency class:  $-1$ (not nilpotent)
Generators:  (1,2,4)(3,6,5), (1,2,3,4,5,6,7)
$|\Aut(F/K)|$:  $1$

Low degree resolvents

|G/N|Galois groups for stem field(s)
3:  $C_3$

Resolvents shown for degrees $\leq 47$

Subfields

Prime degree - none

Low degree siblings

21T2

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 $ $1$ $1$ $()$
$ 3, 3, 1 $ $7$ $3$ $(2,3,5)(4,7,6)$
$ 3, 3, 1 $ $7$ $3$ $(2,5,3)(4,6,7)$
$ 7 $ $3$ $7$ $(1,2,3,4,5,6,7)$
$ 7 $ $3$ $7$ $(1,4,7,3,6,2,5)$

Group invariants

Order:  $21=3 \cdot 7$
Cyclic:  No
Abelian:  No
Solvable:  Yes
GAP id:  [21, 1]
Character table:    
     3  1  1  1  .  .
     7  1  .  .  1  1

       1a 3a 3b 7a 7b
    2P 1a 3b 3a 7a 7b
    3P 1a 1a 1a 7b 7a
    5P 1a 3b 3a 7b 7a
    7P 1a 3a 3b 1a 1a

X.1     1  1  1  1  1
X.2     1  A /A  1  1
X.3     1 /A  A  1  1
X.4     3  .  .  B /B
X.5     3  .  . /B  B

A = E(3)^2
  = (-1-Sqrt(-3))/2 = -1-b3
B = E(7)+E(7)^2+E(7)^4
  = (-1+Sqrt(-7))/2 = b7