Abstract
Let G = (V, E) be a digraph and f a mapping from E into an Abelian group A. Associated with f is its boundary ∂f, a mapping from V to A, defined by ∂f(x) = Σe leaving xf(e)-Σe entering xf(e). We say that G is A-connected if for every b: V → A with Σx ∈ Vb(x)=0 there is an f: E → A - {0} with b = ∂f. This concept is closely related to the theory of nowhere-zero flows and is being studied here in light of that theory.
Original language | American English |
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Pages (from-to) | 165-182 |
Number of pages | 18 |
Journal | Journal of Combinatorial Theory. Series B |
Volume | 56 |
Issue number | 2 |
DOIs | |
State | Published - Nov 1992 |