A Nameless Number
Library Home || Full Table of Contents || Suggest a Link || Library Help
|Triangle-free polygon dissections are a variant of the dissection questions of Catalan, Schroeder, and others: In a convex (n+2)-gon with n+2 labeled nodes, what is a(n), the number of ways of drawing non-intersecting diagonals so that no triangles are formed? This question resonates somewhat with the parallel universe of "triangle-free graphs." With a formulation using geometric recurrences, and Mathematica code for the sequence of the number of (non-crossing) diagonal placements in the (n+3)-gon with vertices 1, 2, ..., n+3 such that no triangles appear.|
|Levels:||High School (9-12), College|
|Math Topics:||Constructions, Triangles and Other Polygons, Sequences and Sets|
© 1994- The Math Forum at NCTM. All rights reserved.