Vertex-Disjoint Copies of K1 + (K1 ∪K2) in Graphs

نویسندگان

  • Shinya Fujita
  • S. FUJITA
چکیده

Let S denote the graph obtained from K4 by removing two edges which have an endvertex in common. Let k be an integer with k ≥ 2. Let G be a graph with |V (G)| ≥ 4k and σ2(G) ≥ |V (G)|/2 + 2k− 1, and suppose that G contains k vertex-disjoint triangles. In the case where |V (G)| = 4k+2, suppose further that G K4t+3 ∪ K4k−4t−1 for any t with 0 ≤ t ≤ k − 1. Under these assumptions, we show that G contains k vertex-disjoint copies of S. AMS 1991 Mathematics Subject Classification. 05C70.

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تاریخ انتشار 2002