arXiv math/94092061994-09-06math.LO

Universal bridge-free graphs

Martin Goldstern, Menachem Kojman

英文摘要：

We prove that there is no countable universal $B_n$-free graph for all $n$ and that there is no countable universal graph in the class of graphs omitting all cycles of length at most $2k$ for $k\ge 2$.

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