Proof of `Formal forward and reverse rows of a unary mixer test` (1st statement)
What this proof establishes
no assumptions
Assuming the claims on the left, the claim on the right holds — checked by the archive's pipeline. Proof code is not displayed here.
Description
Every formal block has a nonsingular middle matrix. Their polar maps are jointly injective. Counting the two row halves, the two orders, the J mixer copies, and the incident components gives the exact rank.