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arXiv · 0910.5652

Bass-Serre theory and counting rank two amalgams

Rieuwert J. Blok·Corneliu Hoffman
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Abstract

An amalgam of groups can be viewed as a Sudoku game inside a group. You are given a set of subgroups and their intersections and you need to decide what the largest group containing such a structure can be. In a recent paper (0907.1388v1) we used Bass-Serre theory of graphs of groups to classify all possible amalgams of Curtis-Tits shape with a given diagram. This note describes the method for general rank two amalgams.

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Rieuwert J. Blok, Corneliu Hoffman. 2009-10-29. Bass-Serre theory and counting rank two amalgams. https://arxiv.org/abs/0910.5652

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