Properties

Label 20T13
20T13 1 3 1->3 13 1->13 2 4 2->4 14 2->14 5 3->5 7 3->7 6 4->6 8 4->8 5->2 5->8 6->1 6->7 9 7->9 16 7->16 10 8->10 15 8->15 9->10 11 9->11 12 10->12 11->3 11->13 12->4 12->14 13->15 18 13->18 14->16 17 14->17 15->12 15->17 16->11 16->18 17->5 20 17->20 18->6 19 18->19 19->1 19->20 20->2
Degree $20$
Order $40$
Cyclic no
Abelian no
Solvable yes
Primitive no
$p$-group no
Group: $C_2\times F_5$

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Copy content magma:G := TransitiveGroup(20, 13);
 

Group invariants

Abstract group:  $C_2\times F_5$
Copy content magma:IdentifyGroup(G);
 
Order:  $40=2^{3} \cdot 5$
Copy content magma:Order(G);
 
Cyclic:  no
Copy content magma:IsCyclic(G);
 
Abelian:  no
Copy content magma:IsAbelian(G);
 
Solvable:  yes
Copy content magma:IsSolvable(G);
 
Nilpotency class:   not nilpotent
Copy content magma:NilpotencyClass(G);
 

Group action invariants

Degree $n$:  $20$
Copy content magma:t, n := TransitiveGroupIdentification(G); n;
 
Transitive number $t$:  $13$
Copy content magma:t, n := TransitiveGroupIdentification(G); t;
 
Parity:  $1$
Copy content magma:IsEven(G);
 
Primitive:  no
Copy content magma:IsPrimitive(G);
 
$\card{\Aut(F/K)}$:  $4$
Copy content magma:Order(Centralizer(SymmetricGroup(n), G));
 
Generators:  $(1,13,18,6)(2,14,17,5)(3,7,16,11)(4,8,15,12)(9,10)(19,20)$, $(1,3,5,8,10,12,14,16,18,19)(2,4,6,7,9,11,13,15,17,20)$
Copy content magma:Generators(G);
 

Low degree resolvents

$\card{(G/N)}$Galois groups for stem field(s)
$2$:  $C_2$ x 3
$4$:  $C_4$ x 2, $C_2^2$
$8$:  $C_4\times C_2$
$20$:  $F_5$

Resolvents shown for degrees $\leq 47$

Subfields

Degree 2: $C_2$ x 3

Degree 4: $C_2^2$

Degree 5: $F_5$

Degree 10: $F_5$, $F_{5}\times C_2$ x 2

Low degree siblings

10T5 x 2, 20T9, 40T14

Siblings are shown with degree $\leq 47$

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

Conjugacy classes

LabelCycle TypeSizeOrderIndexRepresentative
1A $1^{20}$ $1$ $1$ $0$ $()$
2A $2^{10}$ $1$ $2$ $10$ $( 1,12)( 2,11)( 3,14)( 4,13)( 5,16)( 6,15)( 7,17)( 8,18)( 9,20)(10,19)$
2B $2^{10}$ $5$ $2$ $10$ $( 1, 3)( 2, 4)( 5,19)( 6,20)( 7,17)( 8,18)( 9,15)(10,16)(11,13)(12,14)$
2C $2^{8},1^{4}$ $5$ $2$ $8$ $( 1,18)( 2,17)( 3,16)( 4,15)( 5,14)( 6,13)( 7,11)( 8,12)$
4A1 $4^{4},2^{2}$ $5$ $4$ $14$ $( 1, 6,18,13)( 2, 5,17,14)( 3,11,16, 7)( 4,12,15, 8)( 9,10)(19,20)$
4A-1 $4^{4},2^{2}$ $5$ $4$ $14$ $( 1,13,18, 6)( 2,14,17, 5)( 3, 7,16,11)( 4, 8,15,12)( 9,10)(19,20)$
4B1 $4^{4},2^{2}$ $5$ $4$ $14$ $( 1,11)( 2,12)( 3,17,19, 6)( 4,18,20, 5)( 7,10,15,14)( 8, 9,16,13)$
4B-1 $4^{4},2^{2}$ $5$ $4$ $14$ $( 1,20, 5, 7)( 2,19, 6, 8)( 3,13)( 4,14)( 9,16,17,12)(10,15,18,11)$
5A $5^{4}$ $4$ $5$ $16$ $( 1,14, 5,18,10)( 2,13, 6,17, 9)( 3,16, 8,19,12)( 4,15, 7,20,11)$
10A $10^{2}$ $4$ $10$ $18$ $( 1, 8,14,19, 5,12,18, 3,10,16)( 2, 7,13,20, 6,11,17, 4, 9,15)$

Malle's constant $a(G)$:     $1/8$

Copy content magma:ConjugacyClasses(G);
 

Character table

1A 2A 2B 2C 4A1 4A-1 4B1 4B-1 5A 10A
Size 1 1 5 5 5 5 5 5 4 4
2 P 1A 1A 1A 1A 2C 2C 2C 2C 5A 5A
5 P 1A 2A 2B 2C 4A1 4A-1 4B1 4B-1 1A 2A
Type
40.12.1a R 1 1 1 1 1 1 1 1 1 1
40.12.1b R 1 1 1 1 1 1 1 1 1 1
40.12.1c R 1 1 1 1 1 1 1 1 1 1
40.12.1d R 1 1 1 1 1 1 1 1 1 1
40.12.1e1 C 1 1 1 1 i i i i 1 1
40.12.1e2 C 1 1 1 1 i i i i 1 1
40.12.1f1 C 1 1 1 1 i i i i 1 1
40.12.1f2 C 1 1 1 1 i i i i 1 1
40.12.4a R 4 4 0 0 0 0 0 0 1 1
40.12.4b R 4 4 0 0 0 0 0 0 1 1

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Regular extensions

Data not computed