Smallest snarks with oddness 4 and cyclic connectivity 4 have order 44
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منابع مشابه
Smallest snarks with oddness 4 and cyclic connectivity 4 have order 44
The family of snarks – connected bridgeless cubic graphs that cannot be 3edge-coloured – is well-known as a potential source of counterexamples to several important and long-standing conjectures in graph theory. These include the cycle double cover conjecture, Tutte’s 5-flow conjecture, Fulkerson’s conjecture, and several others. One way of approaching these conjectures is through the study of ...
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A snark is a bridgeless cubic graph which is not 3-edge-colourable. The oddness of a bridgeless cubic graph is the minimum number of odd components in any 2factor of the graph. Lukot’ka, Mácajová, Mazák and Škoviera showed in [Electron. J. Combin. 22 (2015)] that the smallest snark with oddness 4 has 28 vertices and remarked and that there are exactly two such graphs of that order. However, thi...
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Tutte’s 5-Flow Conjecture from 1954 states that every bridgeless graph has a nowhere-zero 5-flow. In 2004, Kochol proved that the conjecture is equivalent to its restriction on cyclically 6-edge connected cubic graphs. We prove that every cyclically 6-edge-connected cubic graph with oddness at most 4 has a nowhere-zero 5-flow.
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ژورنال
عنوان ژورنال: Ars Mathematica Contemporanea
سال: 2019
ISSN: 1855-3974,1855-3966
DOI: 10.26493/1855-3974.1601.e75