Abstract
Suppose that G=(V,E) is a graph with even vertices. An even cycle C is a nice cycle of G if G−V(C) has a perfect matching. An orientation of G is a Pfaffian orientation if each nice cycle C has an odd number of edges directed in either direction of the cycle. Let P n and C n denote the path and the cycle on n vertices, respectively. In this paper, we characterize the Pfaffian property of Cartesian products G×P 2n and G×C 2n for any graph G in terms of forbidden subgraphs of G. This extends the results in (Yan and Zhang in Discrete Appl Math 154:145–157, 2006).
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This work is supported by NSFC (No. 10831001; No. 11171279).
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Lu, F., Zhang, L. The Pfaffian property of Cartesian products of graphs. J Comb Optim 27, 530–540 (2014). https://doi.org/10.1007/s10878-012-9533-4
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DOI: https://doi.org/10.1007/s10878-012-9533-4