A Simple Proof of the Karakhanyan-Riordan Theorem on the Discrete Even Torus
نویسندگان
چکیده
We present a simple proof of the result published by V. Karakhanyan [4] and O. Riordan [6] concerning the vertex-isoperimetric problem on the n-dimensional torus. The proof method is a reduction of this problem to a similar problem on some (2n)-dimensional grid, for which a solution is known [3]. We also simplify and clarify the structure of the involved isoperimetric order.
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