Cops and Robbers on Graphs Based on Designs

نویسنده

  • ANTHONY BONATO
چکیده

We investigate the cop number of graphs based on combinatorial designs. Incidence graphs, point graphs, and block intersection graphs are studied, with an emphasis on finding families of graphs with large cop number. We generalize known results on so-called Meyniel extremal families by supplying bounds on the incidence graph of transversal designs, certain G-designs, and BIBDs with λ ≥ 1. Families of graphs with diameter two, C4-free, and with unbounded chromatic number are described with the conjectured asymptotically maximum cop number.

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تاریخ انتشار 2012