论文信息 - Equivalence of the strengthened Hanna Neumann conjecture and the amalgamated graph conjecture

Equivalence of the strengthened Hanna Neumann conjecture and the amalgamated graph conjecture

SummaryWe show that Walter Neumann's strengthened form of Hanna Neumann's conjecture on the best possible upper bound for the rank of the intersection of two subgroups of a free group is equivalent to a conjecture on the best possible upper bound for the number of edges in a bipartite graph with a certain weak symmetry condition. We illustrate the usefulness of this equivalence by deriving relatively easily certain previously known results.

Warren Dicks

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