Longer cycles in essentially 4-connected planar graphs
نویسندگان
چکیده
منابع مشابه
Longer Cycles in Essentially 4-Connected Planar Graphs
A planar 3-connected graph G is called essentially 4-connected if, for every 3-separator S, at least one of the two components of G−S is an isolated vertex. Jackson and Wormald proved that the length circ(G) of a longest cycle of any essentially 4-connected planar graph G on n vertices is at least 2n+4 5 and Fabrici, Harant and Jendrol’ improved this result to circ(G) ≥ 1 2 (n+ 4). In the prese...
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A planar 3-connected graph G is essentially 4-connected if for any 3-separator S of G, one component of the graph obtained from G by removing S is a single vertex. B. Jackson and N.C. Wormald proved that an essentially 4-connected planar graph on n vertices contains a cycle C such that |V (C)| ≥ 2n+4 5 . For a cubic essentially 4-connected planar graph G, B. Grünbaum, J. Malkevitch , and C.-Q. ...
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ژورنال
عنوان ژورنال: Discussiones Mathematicae Graph Theory
سال: 2020
ISSN: 1234-3099,2083-5892
DOI: 10.7151/dmgt.2133