The uniform residual polynomial
Abstract
The exact residual count satisfies Gupta’s total degree bound.
Gupta, arXiv:2607.05567v3, Conjecture 8.3 asks that the remainder for each positive split a+b=d, a at most b, have total degree at most d-3 when d is at least five. Lemma 8.2 identifies one polynomial on every rectangle with m,n at least 2d-1. The remainder counts precisely the normalized integer unit-edge height functions whose strict minima do not all lie on one common physical side.
Theorem 1.1 (Cardinality of each actual fiber).
Lean statement: D5/S3/Combinatorics/Geometry/MiuraResolution.fiber_card_eq_positive_vectors
Proof. Machine-checked in Lean as D5/S3/Combinatorics/Geometry/MiuraResolution.fiber_card_eq_positive_vectors (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Chakshu Gupta (2026). One construction for the Miura-ori flip-graph degree sequence. DOI: 10.48550/arXiv.2607.05567. URL: https://arxiv.org/abs/2607.05567v3.
Commentary.
For all natural a,b,m,n, every K in Core a b, and m,n at least 2(a+b)-1, Nat.card of Fiber a b m n K equals Nat.card of the product PositiveLengths (m-rowOccupied K) (rowRuns K) and PositiveLengths (n-colOccupied K) (colRuns K). The actual equivalence core_positive_vectors_equiv has precisely this fiber as its target, including the complete original height function, JointReduction and the equivalence for every individual physical side. Nat.card_congr therefore applies directly; no quotient, selection of representatives or cardinality assumption is introduced.
Theorem 1.2 (The same polynomial counts the original arrays).
Lean statement: D5/S3/Combinatorics/Geometry/MiuraResolution.core_polynomial_counts_residual
Proof. Machine-checked in Lean as D5/S3/Combinatorics/Geometry/MiuraResolution.core_polynomial_counts_residual (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Chakshu Gupta (2026). One construction for the Miura-ori flip-graph degree sequence. DOI: 10.48550/arXiv.2607.05567. URL: https://arxiv.org/abs/2607.05567v3.
Commentary.
For all natural a,b,m,n with a,b positive, a+b at least five, and m,n at least 2(a+b)-1, evaluation of corePolynomial a b at the rational pair (m,n) equals the rational cast of the unchanged residualCount a b m n. The actual partition residualCoreEquiv places every array in exactly one actual Core fiber. residual_count_eq_sum_fibers gives the sum of these cardinalities. The fiber equality above identifies that sum with core_polynomial_eval. Its positive-vector evaluations use positive_lengths_card and the existing binomial polynomial identities, with all feasibility bounds proved for these same cores.
Theorem 1.3 (The complete original polynomial assertion).
Proof. Machine-checked in Lean as D5/S3/Combinatorics/Geometry/MiuraResolution.result (✓ std3). ∎
Resolves. Problems/gupta-2026-miura-residual-degree-conjecture-83 (proved) by D5/S3/Combinatorics/Geometry/MiuraResolution.result.
Source. Repository-derived.
Acknowledgement. Chakshu Gupta (2026). One construction for the Miura-ori flip-graph degree sequence. DOI: 10.48550/arXiv.2607.05567. URL: https://arxiv.org/abs/2607.05567v3.
Commentary.
For every natural d at least five and positive natural a,b with a+b=d and a at most b, there exists a rational bivariate polynomial of total degree at most d-3 which counts the exact residual class for every natural m,n at least 2d-1. The polynomial is corePolynomial a b, a finite sum over the individual bounded actual cores; it is chosen before either evaluation dimension. core_polynomial_degree_le gives its strict total degree bound, and core_polynomial_counts_residual supplies every evaluation. The argument also establishes the evaluations without using the order of a and b; the conclusion retains the original ordered-split condition.
Here residualCount counts every individual function h from Fin m times Fin n to the integers with h(0,0)=0 and absolute difference exactly one across each Manhattan edge. Strict minima and maxima test all existing neighbours, including the two neighbours of a corner and the three neighbours of a noncorner boundary cell. Their exact cardinalities are a and b. The condition is the negation of the existence of one common side containing every minimum: top has first coordinate one, bottom first coordinate m, left second coordinate one, and right second coordinate n in physical coordinates. A corner belongs to both incident sides. The condition permits minima on several boundary sides and introduces no symmetry quotient or orientation identification.
In the formula, eval uses the assignment i to m if i=0 and to n otherwise, with both dimensions cast to the rationals. The count also has its rational cast. All subtractions in the dimension and degree bounds are natural-number subtractions.
References
- Truth anchor:
D5/S3/Combinatorics/Geometry/MiuraResolution.core_polynomial_counts_residual - Truth anchor:
D5/S3/Combinatorics/Geometry/MiuraResolution.fiber_card_eq_positive_vectors - Truth anchor:
D5/S3/Combinatorics/Geometry/MiuraResolution.result - Dependency: D5/S3/Combinatorics/Geometry/MiuraFiberEquiv
- Dependency: D5/S3/Combinatorics/Geometry/MiuraPartitionCount