منابع مشابه
Subpath acyclic digraphs
A characterization is given for acyclic digraphs that are the acyclic intersection digraphs of subpaths of a directed tree.
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An acyclic set in a digraph is a set of vertices that induces an acyclic subgraph. In 2011, Harutyunyan conjectured that every planar digraph on n vertices without directed 2-cycles possesses an acyclic set of size at least 3n/5. We prove this conjecture for digraphs where every directed cycle has length at least 8. More generally, if g is the length of the shortest directed cycle, we show that...
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ژورنال
عنوان ژورنال: Czechoslovak Mathematical Journal
سال: 1983
ISSN: 0011-4642,1572-9141
DOI: 10.21136/cmj.1983.101867