The trivial group, denoted or , sometimes also called the identity group, is the unique (up to isomorphism) group containing exactly one element , the identity element. Examples include the zero group (which is the singleton set with respect to the trivial group structure defined by the addition ), the multiplicative group (where ), the point group , and the integers modulo 1 under addition. When viewed as a permutation group on letters, the trivial group consists of the single element which fixes each letter.
The trivial group is (trivially) Abelian and cyclic.
The multiplication table for is given below.
1 | |
1 | 1 |
The trivial group has the single conjugacy class and the single subgroup .