(1,{\lambda})-embedded graphs and the acyclic edge choosability

نویسندگان

  • Xin Zhang
  • Guizhen Liu
  • Jian-Liang Wu
چکیده

A (1, λ)-embedded graph is a graph that can be embedded on a surface with Euler characteristic λ so that each edge is crossed by at most one other edge. A graph G is called α-linear if there exists an integral constant β such that e(G′) ≤ αv(G′) + β for each G′ ⊆ G. In this paper, it is shown that every (1, λ)-embedded graph G is 4-linear for all possible λ, and is acyclicly edge-(3∆(G) + 70)-choosable for λ = 1, 2.

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تاریخ انتشار 2011