In this paper, we prove that if G is a plane graph without 4-, 5- and 7-circuits and without intersecting triangles, then for each face f of degree at most 11, any 3-coloring of the boundary of f can be extended to G....In this paper, we prove that if G is a plane graph without 4-, 5- and 7-circuits and without intersecting triangles, then for each face f of degree at most 11, any 3-coloring of the boundary of f can be extended to G. This gives a positive support to a conjecture of Borodin and Raspaud which claims that each plane graph without 5-circuits and intersecting triangles is 3-colorable.展开更多
文摘In this paper, we prove that if G is a plane graph without 4-, 5- and 7-circuits and without intersecting triangles, then for each face f of degree at most 11, any 3-coloring of the boundary of f can be extended to G. This gives a positive support to a conjecture of Borodin and Raspaud which claims that each plane graph without 5-circuits and intersecting triangles is 3-colorable.
