Proof of `Formal forward and reverse rows of a unary mixer test` (3rd 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
Expand the atom's incident components in the two orders of the mixer sum. The symmetric component factorization turns each forward or reverse contribution into precisely its indexed formal product.