Pack L shapes of short sides 1, 2, …, n into the smallest square. Each piece consists of three squares. Pieces may fit into each other’s notches, but their interiors cannot overlap.
Expanded to n=50 on November 1, with 48 competitive instances. The added n=21–50 instances count toward this week, with the deadline unchanged. Cases n=1 and 2 are proved optimal. Cases n=3–20 cite Friedman’s table; n=21–50 have no cited external record. Ordinary starting layouts are provided.