A Kautz graph is a labeled graph, vertices are labeled by strings of length
n+1 above an alphabet with m+1 letters, with the restriction
that every two consecutive letters in the string must be different. There is
a directed edge from a vertex v to another vertex w if it is
possible to transform the string of v into the string of w by
removing the first letter and appending a letter to it.
Kautz graphs have some interesting properties, see eg. Wikipedia for
details.