In this article, we study cycle coverings and 2-factors of a claw-free graph and those of its closure, which has been defined by the first author (On a closure concept in claw-free graphs, J Combin Theory Ser B 70 (1997), 217-224). For a claw-free graph G and its closure cl(G), We prove: (1) V (G) is covered by #kappa# cycles in G if and only if V (cl(G)) is covered by #kappa# cycles of cl(G); and (2) G has a 2-factor with at most #kappa# components if and only if cl(G) has a 2-factor with at most #kappa# components.
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机译:在本文中,我们研究了无爪图及其闭合的2个因数的周期覆盖率和2个因子的影响,该周期覆盖率和闭合率由第一作者定义(关于无爪图的闭合概念,J Combin Theory Ser B 70( 1997),217-224)。对于无爪图G及其闭合cl(G),我们证明:(1)当且仅当V(cl(G))被#kappa覆盖时,V(G)被G中的#kapp#个环覆盖。 cl(G)个循环; (2)当且仅当cl(G)具有最多#kappa#个成分的2因子时,G才具有最多#kapp#个成分的2因子。
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