Conditions for the existence of a 6-cycle system of Kn-E(F) for any spanning forest F of Kn were discussed. Here, F is a leave and a forest is defined as the graph that contains no cycle. It was shown that when the leave is a forest, it must be that n is even. Results obtaining m-cycle systems of graphs that are close to complete, were obtained when m is odd, with each vertex having even degree in the leave.
- Cycle systems