Decompositions into two paths

نویسنده

  • Zdzislaw Skupien
چکیده

It is proved that a connected multigraph G which is the union of two edge-disjoint paths has another decomposition into two paths with the same set, U , of endvertices provided that the multigraph is neither a path nor cycle. Moreover, then the number of such decompositions is proved to be even unless the number is three, which occurs exactly if G is a tree homeomorphic with graph of either symbol + or ⊥. A multigraph on n vertices with exactly two traceable pairs is constructed for each n ≥ 3. The Thomason result on hamiltonian pairs is used and is proved to be sharp.

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عنوان ژورنال:
  • Discussiones Mathematicae Graph Theory

دوره 25  شماره 

صفحات  -

تاریخ انتشار 2005