Regular sets of circulant quartic graphs

A. Abdollahi, J. Bagherian, F. Jafari +3

For a graph $\Gamma =(V,E)$ and nonnegative integers $a$ and $b$, a nonempty proper subset $C\subset V$ is called an $(a,b)$-regular set if every vertex in $C$ has exactly $a$ neighbors…