rank 3: n=1, forms (rhombi + coordinates)=10, candidates z=2 (max coordinate 1), level-2 boxes: 4
boxes tested per level: [(2, 4)]; boxes of the partition per level: [(2, 4)]; total 4; volume 1; unresolved: []; distinct z used: 1; 0.1s
RESULT rank 3: [0,1)^1 is partitioned into 4 half-open dyadic boxes, each contained in an integer translate of U+ (certificate cover_r3.json). Hence (ii+) and (ii) hold for rank 3; no vertex lemma used.
