Matroid tree graphs and interpolation theorems
โ Scribed by Sanming Zhou
- Publisher
- Elsevier Science
- Year
- 1995
- Tongue
- English
- Weight
- 119 KB
- Volume
- 137
- Category
- Article
- ISSN
- 0012-365X
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โฆ Synopsis
Using the Hamiltonicity of matroid tree graphs we give a new proof for an interpolation theorem of and other related results. From the proof we refine a general approach for dealing with interpolation problems of graphs.
Let G be a simple, connected graph of order p and size q. For each integer m, p-1 <~m<<,q, denote by Cm(G) the set of connected spanning subgraphs of G with m edges. Whenever H~Cm(G), let ~0(H) be the number of pendant vertices of H. Thus, rยข is a mapping from Cm(G) to 7/+, the set of nonnegative integers. If m =p-1, Cm(G) is exactly the set of spanning trees of G. It was first proved in [6,1 that ~p(Cp_ I(G)) is an integer interval. An elegant proof for this result was given in . In general, Barefoot [1] proved the following theorem.
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