A graph is Y βY -reducible if it can be reduced to a vertex by a sequence of series-parallel reductions and Y βY -transformations. Terminals are dis-
Forbidden minors for wye-delta-wye reducibility
β Scribed by Yaming Yu
- Book ID
- 102343527
- Publisher
- John Wiley and Sons
- Year
- 2004
- Tongue
- English
- Weight
- 57 KB
- Volume
- 47
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
A graph is YβΞβY reducible if it can be reduced to a single vertex by a sequence of seriesβparallel reductions and YβΞβY transformations. The class of YβΞβY reducible graphs is minor closed. We found a large number of minor minimal YβΞβY irreducible graphs: a family of 57578 31βedge graphs and another 40βedge graph. It is still an open problem to characterize YβΞβY reducible graphs in terms of a finite set of forbidden minors. Β© 2004 Wiley Periodicals, Inc. J Graph Theory 47: 317β321, 2004
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