【摘 要】
：
Lin-Lu-Yau introduced a notion of Ricci curvature for graphs and obtained a complete classification for all Ricci-flat graphs with girth at least five.In this paper,we characterize all Ricci-flat graphs of girth four with vertex-disjoint 4-cycles.
【机 构】
：
School of Mathematics and Statistics,Guangdong University of Technology,Guangzhou 510520,P.R.China;S
论文部分内容阅读
Lin-Lu-Yau introduced a notion of Ricci curvature for graphs and obtained a complete classification for all Ricci-flat graphs with girth at least five.In this paper,we characterize all Ricci-flat graphs of girth four with vertex-disjoint 4-cycles.
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