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Maximum bipartite subgraphs of Kneser graphs. (English) Zbl 0674.05064
Summary: We investigate the maximum number of edges in a bipartite subgraph of the Kneser graph K(n,r). The exact solution is given for either r arbitrary and $$n\leq (4.3+o(1))r,$$ or $$r=2$$ and n arbitrary. The problem is in connection with the study of the bipartite subgraph polytope of a graph.

##### MSC:
 05C99 Graph theory 05A05 Permutations, words, matrices
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##### References:
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