p-group, cyclic, abelian, monomial
Aliases: C4, also denoted Z4, rotations of a square, SmallGroup(4,1)
Series: Derived ►Chief ►Lower central ►Upper central ►Jennings
| C1 — C4 | 
| C1 — C4 | 
| C1 — C4 | 
Generators and relations for C4
 G = < a | a4=1 >
Character table of C4
| class | 1 | 2 | 4A | 4B | |
| size | 1 | 1 | 1 | 1 | |
| ρ1 | 1 | 1 | 1 | 1 | trivial | 
| ρ2 | 1 | 1 | -1 | -1 | linear of order 2 | 
| ρ3 | 1 | -1 | -i | i | linear of order 4 faithful | 
| ρ4 | 1 | -1 | i | -i | linear of order 4 faithful | 
(1 2 3 4)
G:=sub<Sym(4)| (1,2,3,4)>;
G:=Group( (1,2,3,4) );
G=PermutationGroup([[(1,2,3,4)]])
G:=TransitiveGroup(4,1);
C4 is a maximal subgroup of
 C8  D4  C32⋊C4  C72⋊C4  C112⋊C4
 Dicp: Q8  Dic3  Dic5  Dic7  Dic11  Dic13  Dic17  Dic19 ...
 Cp⋊C4, p=1 mod 4: F5  C13⋊C4  C17⋊C4  C29⋊C4  C37⋊C4  C41⋊C4  C53⋊C4  C61⋊C4 ...
C4 is a maximal quotient of 
 C8  C32⋊C4  C72⋊C4  A5⋊C4  C112⋊C4
 Dicp: Dic3  Dic5  Dic7  Dic11  Dic13  Dic17  Dic19  Dic23 ...
 Cp⋊C4, p=1 mod 4: F5  C13⋊C4  C17⋊C4  C29⋊C4  C37⋊C4  C41⋊C4  C53⋊C4  C61⋊C4 ...
| action | f(x) | Disc(f) | 
|---|---|---|
| 4T1 | x4-5x2+5 | 24·53 | 
Matrix representation of C4 ►in GL1(𝔽5) generated by
| 2 | 
G:=sub<GL(1,GF(5))| [2] >;
C4 in GAP, Magma, Sage, TeX
C_4
% in TeX
G:=Group("C4"); // GroupNames label
G:=SmallGroup(4,1);
// by ID
G=gap.SmallGroup(4,1);
# by ID
G:=PCGroup([2,-2,-2,4]:ExponentLimit:=1);
// Polycyclic
G:=Group<a|a^4=1>;
// generators/relations
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