Some Comments on Co Graphs and Ci Index
نویسنده
چکیده
In [13] co graphs are introduced and a formula is given for the PI index of these graphs. Based on this formula a new topological CI index is proposed. In this note it is observed that co graphs are precisely isometric subgraphs of hypercubes alias partial cubes. Some fact about partial cubes and their uses in chemical graph theory are listed. A couple of comments on the CI index are also given. ————————————————— ∗Supported in part by the Ministry of Science of Slovenia under the grant P1-0297.
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