The compression to three integers holds at every root of unity, and there it is proved
- what
Part IV's alphabet,
(1,−1,t,t⁻¹), is the second member of a family: the full set of t-th roots of unity together with one free reciprocal pair. arXiv:2608.09619 evaluatess_λ(μ_t, z, z⁻¹)for every t ≥ 2 and every λ, with no hypothesis on the shape: the value is a signed product of exactly three factors over a fixed denominator, or zero, and the three arguments are read off the t-quotient of λ. At t = 2 the alphabet is Part IV's. (The letter t changes job between the two papers: in Part IV it is the free variable, there the order of the root of unity.)- why
Part IV grades its closed form an Observation: checked against the bialternant in exact arithmetic on all 3060 partitions with four parts ≤ 14 and all 4845 with parts ≤ 16, with no mismatch, and not proved. The general statement carries a proof — a Laplace expansion along the t frozen rows of the bialternant with one cancellation lemma in the symmetric group, which also delivers the sign, the one already in Littlewood's evaluation at the roots of unity.
- so
No number in Part IV moves and its record does not need a new version. What moves is a status word: at t = 2 the closed form stops being an Observation.
The rank-two case Part IV stopped at, and said so, is now conjectured to be unrepairable rather than merely unrepaired: Conjecture 10.4 there says the value is a product of characters for every λ if and only if the free part is a single reciprocal pair. Four deformations of the alphabet are measured against it and each destroys the product. That is evidence, not a proof, and it is labelled a conjecture.
- check
- the paper, and the scripts with their archived output at schur-orbit-and-reciprocal-pair —
theorem_full.py: 959 exact values, 476 zeros, 0 sign failures, 0 magnitude failures