Packings of

Every packing known for this n, oldest to newest. Click one to make it the left side (blue), shift-click for the right (gold); the slider morphs between them, with each square matched to its nearest counterpart. Squares that end up in a different place are outlined.

morph

Matching is by position and angle; when two packings are "alternatives" rather than rearrangements, some squares necessarily swap places during the morph — the morph is a visual aid, not a physical motion.