MathDB
Infintiely many polygons coinciding with P_0

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November 21, 2010
combinatorics proposedcombinatorics

Problem Statement

Let P0=A0A1An1\mathcal{P}_0=A_0A_1\ldots A_{n-1} be a convex polygon such that AiAi+1=2[i/2]A_iA_{i+1}=2^{[i/2]} for i=0,1,,n1i=0, 1,\ldots ,n-1 (where An=A0A_n=A_0). Define the sequence of polygons Pk=A0kA1kAn1k\mathcal{P}_k=A_0^kA_1^k\ldots A_{n-1}^k as follows: Ai1A_i^1 is symmetric to AiA_i with respect to A0A_0, Ai2A_i^2 is symmetric to Ai1A_i^1 with respect to A11A_1^1, Ai3A_i^3 is symmetric to Ai2A_i^2 with respect to A22A_2^2 and so on. Find the values of nn for which infinitely many polygons Pk\mathcal{P}_k coincide with P0\mathcal{P}_0.