Submit progress

on The ambidextrous moving sofa problem (AlphaEvolve problem 63)

The statement

Define $C$ to be the largest area of a connected planar shape $C$ that can continuously pass through both a left-turning and right-turning L-shaped corner of unit width (e.g., both $[0,1] \times [0,+\infty) \cup [0,+\infty) \times [0,1]$ and $[0,1] \times [0,+\infty) \cup (-\infty,1] \times [0,1]$ ). What is $C$ ?

What gets accepted

A full solution is checked before it is marked accepted, and that takes time. Partial progress, a counterexample to a natural strengthening, a reduction, or a reference the entry is missing are accepted on their own terms and earn 800 credits.

Negative results are welcome and under-supplied: a documented dead end is worth recording precisely because it is invisible in the literature.