Nowhere-zero integral chains and flows in bidirected graphs
نویسندگان
چکیده
منابع مشابه
Nowhere zero flows in line graphs
Cai an Corneil (Discrete Math. 102 (1992) 103–106), proved that if a graph has a cycle double cover, then its line graph also has a cycle double cover, and that the validity of the cycle double cover conjecture on line graphs would imply the truth of the conjecture in general. In this note we investigate the conditions under which a graph G has a nowhere zero kow would imply that L(G), the line...
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We study the flow spectrum S(G) and the integer flow spectrum S(G) of odd regular graphs. We show that there are signed graphs where the difference between the integer flow number and the flow number is greater than or equal to 1, disproving a conjecture of Raspaud and Zhu [7]. Let G be a (2t + 1)-regular graph. We show that if r ∈ S(G), then r = 2 + 1t or r ≥ 2 + 2 2t−1 . This result generaliz...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 1987
ISSN: 0095-8956
DOI: 10.1016/0095-8956(87)90032-3