Properties

Label 20T4
Order \(20\)
n \(20\)
Cyclic No
Abelian No
Solvable Yes
Primitive No
$p$-group No
Group: $D_{10}$

Related objects

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Group action invariants

Degree $n$ :  $20$
Transitive number $t$ :  $4$
Group :  $D_{10}$
Parity:  $1$
Primitive:  No
Nilpotency class:  $-1$ (not nilpotent)
Generators:  (1,15)(2,16)(3,14)(4,13)(5,12)(6,11)(7,10)(8,9)(17,19)(18,20), (1,4,6,8,10,12,14,16,18,19)(2,3,5,7,9,11,13,15,17,20)
$|\Aut(F/K)|$:  $20$

Low degree resolvents

|G/N|Galois groups for stem field(s)
2:  $C_2$ x 3
4:  $C_2^2$
10:  $D_{5}$

Resolvents shown for degrees $\leq 47$

Subfields

Degree 2: $C_2$ x 3

Degree 4: $C_2^2$

Degree 5: $D_{5}$

Degree 10: $D_5$, $D_{10}$ x 2

Low degree siblings

10T3 x 2

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 $ $1$ $1$ $()$
$ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 $ $5$ $2$ $( 1, 2)( 3,19)( 4,20)( 5,18)( 6,17)( 7,16)( 8,15)( 9,14)(10,13)(11,12)$
$ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 $ $5$ $2$ $( 1, 3)( 2, 4)( 5,19)( 6,20)( 7,18)( 8,17)( 9,16)(10,15)(11,14)(12,13)$
$ 10, 10 $ $2$ $10$ $( 1, 4, 6, 8,10,12,14,16,18,19)( 2, 3, 5, 7, 9,11,13,15,17,20)$
$ 5, 5, 5, 5 $ $2$ $5$ $( 1, 6,10,14,18)( 2, 5, 9,13,17)( 3, 7,11,15,20)( 4, 8,12,16,19)$
$ 10, 10 $ $2$ $10$ $( 1, 8,14,19, 6,12,18, 4,10,16)( 2, 7,13,20, 5,11,17, 3, 9,15)$
$ 5, 5, 5, 5 $ $2$ $5$ $( 1,10,18, 6,14)( 2, 9,17, 5,13)( 3,11,20, 7,15)( 4,12,19, 8,16)$
$ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 $ $1$ $2$ $( 1,12)( 2,11)( 3,13)( 4,14)( 5,15)( 6,16)( 7,17)( 8,18)( 9,20)(10,19)$

Group invariants

Order:  $20=2^{2} \cdot 5$
Cyclic:  No
Abelian:  No
Solvable:  Yes
GAP id:  [20, 4]
Character table:   
     2  2  2  2   1   1   1   1  2
     5  1  .  .   1   1   1   1  1

       1a 2a 2b 10a  5a 10b  5b 2c
    2P 1a 1a 1a  5a  5b  5b  5a 1a
    3P 1a 2a 2b 10b  5b 10a  5a 2c
    5P 1a 2a 2b  2c  1a  2c  1a 2c
    7P 1a 2a 2b 10b  5b 10a  5a 2c

X.1     1  1  1   1   1   1   1  1
X.2     1 -1 -1   1   1   1   1  1
X.3     1 -1  1  -1   1  -1   1 -1
X.4     1  1 -1  -1   1  -1   1 -1
X.5     2  .  .   A -*A  *A  -A -2
X.6     2  .  .  *A  -A   A -*A -2
X.7     2  .  . -*A  -A  -A -*A  2
X.8     2  .  .  -A -*A -*A  -A  2

A = -E(5)-E(5)^4
  = (1-Sqrt(5))/2 = -b5