Ring:Z4

Definition
This ring, denoted $$\Z_4$$ or $$\Z/4\Z$$, is defined as the quotient of the ring of integers by the multiples of $$4$$.

Note that the symbols $$\Z_4$$ and $$\Z/4\Z$$ are also used for the additive group of this ring, which is the cyclic group of order four.

GAP implementation
The ring can be defined using GAP's ZmodnZ function:

ZmodnZ(4)