Scalar certificates for the graph bounds #
Keeping these integer and real arguments independent of graph definitions lets them elaborate while the graph infrastructure builds.
The sharp strip cubic. The single-variable inequality the n ≥ 123 region arithmetic
bottoms out at, after X is pushed to its master maximum and H to the end of its range.
Substituting N = 123 + u makes every coefficient non-negative
(1068496017 + 1122649307u + 11552736u² + 20700u³), giving an explicit positive certificate.
The two-variable core. After both X-eliminations the target is a cubic in (N, H):
4608000·(N−H)² < 38400·(N−H)·(Q+120) + 23·P·Q², P = 6N+160−23H, Q = 16N+7H−150.
Every H-coefficient of the gap is negative at N ≥ 123, so the minimum is at 17H = 4N − 200,
and 4913·gap − cubic is identically 289(M−17H)(−c₁) + 17(M²−(17H)²)(−c₂) + (M³−(17H)³)·25921
with M = 4N − 200, −c₁ = 104512N² − 11944120N + 18478500 ≥ 0 (its larger root is ≈ 112.7)
and −c₂ = 111734N + 3585580 ≥ 0. So linarith closes on those three products plus the cubic.
The R-free core of the sharp strip discharge. On the counting region
(0 ≤ H ≤ X, 10X + 7H ≤ 4N − 200) at N ≥ 123,
4608·(N−H)² < 384·(N−H)·(2N−X−23) + 23·(N−4−X−3H)·(2N−X−35)².
Both X-dependent factors are pushed to the master maximum simultaneously — 10·t ≥ 6N+160−23H
and 10·A ≥ 16N+7H−150, equalities together at X = X_max — and moore_strip_twovar_sharp
closes what is left.
Sigma cross-slot slack #
The two sigma slack budgets absorb the unique crossing cost.