The number of independent sets in unicyclic graphs

نویسندگان

Anders Sune Pedersen

Preben D. Vestergaard

چکیده

In this paper, we determine upper and lower bounds for the number of independent sets in a unicyclic graph in terms of its order. This gives an upper bound for the number of independent sets in a connected graph which contains at least one cycle. We also determine the upper bound for the number of independent sets in a unicyclic graph in terms of order and girth. In each case we characterize the extremal graphs.

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