A NOTE ON REGULAR SETS IN CAYLEY GRAPHS

Abstract A subset R of the vertex set a graph $\Gamma $ is said to be $(\kappa ,\tau )$ -regular if induces $\kappa subgraph and every outside adjacent exactly $\tau vertices in . In particular, some Cayley on finite group G , then called Let H nontrivial normal subgroup pair integers satisfying $0\leq \kappa \leq |H|-1$ $1\leq \tau |H|$ $\gcd (2,|H|-1)\mid It proved that (i) even, ; (ii) odd, only it $(0,1)$