Tutte's 5-flow conjecture for graphs of nonorientable genus 5
نویسنده
چکیده
We develop four constructions for nowhere-zero 5-ows of 3-regular graphs which satisfy special structural conditions. Using these constructions we show a minimal counterexample to Tutte's 5-ow conjecture is of order 44 and therefore every bridgeless graph of nonorientable genus 5 has a nowhere-zero 5-ow. One of the structural properties is formulated in terms of the structure of the multigraph G(F) obtained from a given 3-regular graph G by contracting the circles of a 2-factor F in G.
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عنوان ژورنال:
- Journal of Graph Theory
دوره 22 شماره
صفحات -
تاریخ انتشار 1996