Labeled Binary Planar Trees
نویسنده
چکیده
We study the natural map η between a group of binary planar trees whose leaves are labeled by elements of a free abelian group H and a certain group D(H) derived from the free Lie algebra over H. Both of these groups arise in several different topological contexts. η is known to be an isomorphism over Q, but not over Z. We determine its cokernel and attack the conjecture that it is injective.
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تاریخ انتشار 2006