Groups of order 1

This article gives information about, and links to more details on, groups of order 1
See pages on algebraic structures of order 1| See pages on groups of a particular order

There is, up to isomorphism, a unique group of order 1, namely the trivial group. In fact, it is, up to isomorphism, the unique magma of order 1. We can see this by noting that the multiplication table on any one-element set is completely constrained.