The 3-path-step Operator on Trees and Unicyclic Graphs
نویسنده
چکیده
E.Prisner in his book Graph Dynamics defines the k-path-step operator on the class of finite graphs. The k-path-step operator (for a positive integer k) is the operator S′ k which to every finite graph G assigns the graph S′ k(G) which has the same vertex set as G and in which two vertices are adjacent if and only if there exists a path of length k in G connecting them. In the paper the trees and the unicyclic graphs fixed in the operator S′ 3 are studied.
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