Let G be a connected graph of order n, and NC2(G) denote min{|N(u)U(v) |:dist(u,v) = 2}, where dist(u,v) is the distance between u and v in G. A cycle C in Gis called a dominatiny cycle, if V(G)\V(C) is an independent...Let G be a connected graph of order n, and NC2(G) denote min{|N(u)U(v) |:dist(u,v) = 2}, where dist(u,v) is the distance between u and v in G. A cycle C in Gis called a dominatiny cycle, if V(G)\V(C) is an independent set in G. In this paper, weprove that if G contains a domillating cycle and 2, then G contains a dominating cycleof length at least min{n, 2NC2(G) - 2}, which proves partially a conjecture of R. Shenand F. Tian. And we give a class of graphs that show the result is shrpg.展开更多
文摘Let G be a connected graph of order n, and NC2(G) denote min{|N(u)U(v) |:dist(u,v) = 2}, where dist(u,v) is the distance between u and v in G. A cycle C in Gis called a dominatiny cycle, if V(G)\V(C) is an independent set in G. In this paper, weprove that if G contains a domillating cycle and 2, then G contains a dominating cycleof length at least min{n, 2NC2(G) - 2}, which proves partially a conjecture of R. Shenand F. Tian. And we give a class of graphs that show the result is shrpg.
