The size of bipartite graphs with girth eight

نویسنده

  • Stefan Neuwirth
چکیده

Reiman’s inequality for the size of bipartite graphs of girth six is generalised to girth eight. It is optimal in as far as it admits the algebraic structure of generalised quadrangles as case of equality. This enables us to obtain the optimal estimate e ∼ v for balanced bipartite graphs. We also get an optimal estimate for very unbalanced graphs.

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تاریخ انتشار 2001