The Classification of Finitely Spreading Graphs
نویسنده
چکیده
Thomassen introduced the concept of a finitely spreading graph: an infinite graph whose edges can be oriented, each in one, both, or neither direction, so that every vertex has finite out-degree and every ray has a forward oriented tail. He conjectured that a graph is finitely spreading if and only if it is bounded in the sense of Halin—equivalently (see [5]), if it contains none of three specified infinitely spreading graphs. We prove Thomassen"s conjecture in amended form, adding a fourth minimal obstruction to the three conjectured ones.
منابع مشابه
The Classi cation of Finitely Spreading Graphs
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