The Largest Sofa You Can Move Around a Corner

If you’ve ever moved into a new home, then you know how difficult it can be to steer bulky furniture through narrow hallways or around awkward corners. Mathematicians have been trying to solve this problem, too, ever since 1966, when Leo Moser framed it in quantitative terms. Say you want to move a two-dimensional shape — your sofa (disregarding its height) — through an L-shaped hallway.

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