More Forbidden Minors for Wye-Delta-Wye Reducibility
نویسنده
چکیده
A graph is Y ∆Y reducible if it can be reduced to isolated vertices by a sequence of series-parallel reductions and Y ∆Y transformations. It is still an open problem to characterize Y ∆Y reducible graphs in terms of a finite set of forbidden minors. We obtain a characterization of such forbidden minors that can be written as clique k-sums for k = 1, 2, 3. As a result we show constructively that the total number of forbidden minors is more than 68 billion up to isomorphism.
منابع مشابه
Index of talks
Invited talks . . . . . . . . . . . . . . . . . . . . . . . . . 11 Bojan Mohar, Rooted K2,4-minors and wye-delta reducibility 11 János Pach, The importance of being simple . . . . . . . 11 Paul Seymour, . . . . . . . . . . . . . . . . . . . . . . . . 12 R. Ravi, Improved Approximations for Graph-TSP in Regular Graphs . . . . . . . . . . . . . . . . . . . . . . . 12 Bruce Reed, The Structure and...
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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 13 شماره
صفحات -
تاریخ انتشار 2006