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Dicyclic group:Dic20

Revision as of 01:53, 16 January 2013 by Vipul (talk | contribs) (Definition)
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This group is defined as the dicyclic group of order 20, and hence degree 5. In other words, it has the presentation:

\langle a,b,c \mid a^5 = b^2 = c^2 = abc \rangle

Alternatively, it has the presentation:

\langle a,b,c \mid a^{10} = e, a^5 = b^2, bab^{-1} = a^{-1} \rangle.

Arithmetic functions

Group properties

Important properties

Property Satisfied? Explanation
cyclic group No
abelian group No
nilpotent group No
metacyclic group Yes
supersolvable group Yes
solvable group Yes

Other properties

Property Satisfied? Explanation
ambivalent group No
Schur-trivial group Yes This is true for all dicyclic groups.
finite group with periodic cohomology Yes This is true for all dicyclic groups.

GAP implementation

Group ID

This finite group has order 20 and has ID 1 among the groups of order 20 in GAP's SmallGroup library. For context, there are 5 groups of order 20. It can thus be defined using GAP's SmallGroup function as:


For instance, we can use the following assignment in GAP to create the group and name it G:

gap> G := SmallGroup(20,1);

Conversely, to check whether a given group G is in fact the group we want, we can use GAP's IdGroup function:

IdGroup(G) = [20,1]

or just do:


to have GAP output the group ID, that we can then compare to what we want.