Abstract
A graph is H-free if it contains no H as a subgraph. The diamond graph is the graph obtained from \(K_4\) by deleting one edge. We prove that if G is a connected graph with order \(n\ge 10\), then there exists a subset \(S\subseteq V(G)\) with \(|S|\le n/5\) such that the subgraph induced by \(V(G)\setminus N[S]\) is diamond-free, where N[S] is the closed neighborhood of S. Furthermore, the bound is sharp.
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This research was supported Science and Technology Commission of Shanghai Municipality (STCSM) Grant 18dz2271000.
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Communicated by Xueliang Li.
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Yan, J. Isolation of the Diamond Graph. Bull. Malays. Math. Sci. Soc. 45, 1169–1181 (2022). https://doi.org/10.1007/s40840-022-01248-6
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DOI: https://doi.org/10.1007/s40840-022-01248-6