CMIMC 2016 Geometry Problem 4

Andrew the Antelope canters along the surface of a regular icosahedron, which has twenty equilateral triangle faces and edge length 4. (A three-dimensional image of an icosahedron is shown to the right.) If he wants to move from one vertex to the opposite vertex, the minimum distance he must travel can be expressed as \sqrt{n} for some integer n. Compute n.

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