e_321121
plain-language theorem explainer
For the concrete multi-index (3,2,1,1,2,1) on Fin 4, the folded coupling numerator equals eight times the tabulated explicit kernel value. Gravity analysts assembling the 4D Regge midpoint M2TT identity cite this as one of the 256 kernel cells. The proof is a single kernel decide on integer arithmetic.
Claim. Let $a,b,c,d,i,j\in\{0,1,2,3\}$. Writing $N$ for the folded coupling numerator and $Z$ for the explicit integer kernel table, one has $N(3,2,1,1,2,1)=8\,Z(3,2,1,1,2,1)$.
background
This module is chunk 14 of a 256-cell kernel certification that the 4D Regge midpoint M2TT numerator equals eight times an explicit integer table. Indices run over Fin 4 (four spacetime directions).
The numerator $N(a,b,c,d,i,j)$ is defined by folding a fixed coupling list: each term contributes an integer via a local contribution map, and the fold starts at 0. The explicit kernel $Z$ is a pattern-matched table on six Fin-4 indices, returning small integers such as $4$, $-2$, and so on for the nonzero support.
The local claim is one concrete cell of the identity $N=8Z$. Upstream, both $N$ and $Z$ are pure definitions in the kernel certificate module; no analytic lemma is required beyond evaluating those definitions at fixed indices.
proof idea
One-line computational proof: decide evaluates both sides at the literal indices $(3,2,1,1,2,1)$ and checks integer equality. No lemmas are invoked; the kernel reduces the fold defining the numerator and the pattern match defining the explicit table to concrete Int values, then confirms they stand in the ratio $8$.
why it matters
Parent theorem is the full assembly m2Num_eq_eight_explicitZ, which states $\forall a,b,c,d,i,j,, N=8Z$ by exhaustive fin_cases on all six indices. Each chunk theorem such as this one discharges one cell so the assembly case split stays modular and kernel-checkable.
In the Recognition gravity stack this identity is bookkeeping for the exact midpoint Regge calculus in 4D: it certifies that the discrete curvature/mass-side numerator matches the closed-form kernel used downstream. It does not itself invoke the forcing chain (T5–T8) or the Recognition Composition Law; it is pure discrete-geometry arithmetic supporting the gravity analysis layer.
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