Abstract
In this paper, we obtain the following result: Let k, n 1 and n 2 be three positive integers, and let G = (V 1,V 2;E) be a bipartite graph with |V1| = n 1 and |V 2| = n 2 such that n 1 ⩾ 2k + 1, n 2 ⩾ 2k + 1 and |n 1 − n 2| ⩽ 1. If d(x) + d(y) ⩾ 2k + 2 for every x ∈ V 1 and y ∈ V 2 with xy \( \notin \) E(G), then G contains k independent cycles. This result is a response to Enomoto’s problems on independent cycles in a bipartite graph.
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This work was supported by the Foundation for the Distinguished Young Scholars of Shandong Province (Grant No. 2007BS01021), the Taishan Scholar Fund from Shandong Province, SRF for ROCS, SEM and National Natural Science Foundation of China (Grant No. 60673047)
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Yan, J., Gao, Y. On Enomoto’s problems in a bipartite graph. Sci. China Ser. A-Math. 52, 1947–1954 (2009). https://doi.org/10.1007/s11425-009-0012-z
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DOI: https://doi.org/10.1007/s11425-009-0012-z