Abstract:
For any two positive integers m, n, we denote
the graph Km,n ⊙ K1 by G. Ma Ke-Jie proposed a conjecture [9]
that pendant edge extension of a complete bipartite graph is a k-
graceful graph for k > 2. In this paper we prove his conjecture for
n 6 m < n2 + ⌊
k
n
⌋ + r.