Four-Exit Raw Pareto Spectrum
Abstract
The raw four-exit family has a complete menu of simultaneously attainable minimal excess vectors.
Theorem 1.1 (The complete actual endpoint menu).
Lean statement: D5/S3/Arith/FibonacciAtomic/FourExitRawParetoSpectrum.result
Proof. Machine-checked in Lean as D5/S3/Arith/FibonacciAtomic/FourExitRawParetoSpectrum.result (✓ std3). ∎
Source. Repository-derived.
Commentary.
For every positive integer k, the literal right-comb family contains a baseline and four exceptional rows A, Y, H, Z at each of k slots. Every row has 8k + 16 compulsory leaves. Costs count the distinct addresses actually requested by a deterministic strategy that terminates and correctly decides membership in the third substitution image on every finite input tree.
The endpoint menu has two kinds of vectors. A first-kind vector is zero at the baseline or at a single Y, H, or Z row, and one elsewhere. A second-kind vector is zero at an A row, two at one of the Y, H, Z rows in that same slot, and one elsewhere. Every correct strategy has cost at least the compulsory leaf count plus one menu vector in every coordinate. Conversely, each menu vector is the exact excess of a single correct strategy simultaneously on all 4k + 1 rows. The coordinatewise minimal actual excess vectors are exactly the menu, whose cardinality is 6k + 1. No assertion is made that every vector above this menu is attainable.
The baseline endpoint uses ordinary scans at all slots. The other endpoints use one of six local five-row recipes, transported to the selected slot’s coordinates and extended by ordinary scans at the remaining slots. Actual joint-response realization supplies a correct strategy with those simultaneous costs. Each endpoint has a unique zero coordinate; endpoints sharing an A zero differ in the location of their two. Thus the menu is an antichain. Domination and attainment identify all minimal actual vectors, and the two endpoint kinds contribute 3k + 1 and 3k distinct vectors.
References
- Truth anchor:
D5/S3/Arith/FibonacciAtomic/FourExitRawParetoSpectrum.result - Dependency: D5/S3/Arith/FibonacciAtomic/FourExitRawDomination
- Dependency: D5/S3/Arith/FibonacciAtomic/FourExitRawEndpointSpectrum
- Dependency: D5/S3/Arith/FibonacciAtomic/FourExitScanExtension