Planar hypohamiltonian oriented graphs
نویسندگان
چکیده
In 1978 Thomassen asked whether planar hypohamiltonian oriented graphs exist. Infinite families of such have since been described but for infinitely many n it remained an open question order this paper we develop new methods constructing digraphs, which, combined with efficient graph generation algorithms, enable us to fully characterise the orders which Our novel also led discover smallest and size, as well orientations maximal graphs. Furthermore, answer a related problem Schiermeyer on vertex degrees in graphs, all hypotraceable
منابع مشابه
Planar hypohamiltonian graphs
A graph is called hypohamiltonian if it is not hamiltonian but, when omitting an arbitrary vertex, it becomes hamiltonian. The smallest hypohamiltonian graph is the famous Petersen graph (found by Kempe in 1886) on 10 vertices. In 1963, Sousselier posed a problem of recreational nature, and thus began the study of hypohamiltonian graphs. Many authors followed, in particular Thomassen with a ser...
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ژورنال
عنوان ژورنال: Journal of Graph Theory
سال: 2021
ISSN: ['0364-9024', '1097-0118']
DOI: https://doi.org/10.1002/jgt.22765