Freiman repeated-three proof: width matrix
ProvedFreiman.lowerJ_width_matrixcertificatesfreimanlower-construction
Cancel the unimodular determinant in the actual full αβ width formula; actual positive denominators are retained.
Preamble
import Definitions.Def_Freiman_lowerJData import Mathlib.Tactic.Linarith import Mathlib.Tactic.Push import Mathlib.Tactic.FinCases open Freiman
Formal statement
theorem Freiman.lowerJ_width_matrix (hf : ∀ (w : List ℕ+) (t : ℝ), 0 < t → prefixEval w t = lowerInitialMatEval (lowerInitialWordMatrix w) t ∧ 0 < lowerInitialMatDen (lowerInitialWordMatrix w) t ∧ (lowerInitialWordMatrix w).a*(lowerInitialWordMatrix w).d - (lowerInitialWordMatrix w).b*(lowerInitialWordMatrix w).c = (-1:ℝ)^w.length) (hb : ∀ w : List ℕ+, (lowerInitialWordMatrix w).c = ((lowerCD w).1:ℝ) ∧ (lowerInitialWordMatrix w).d = ((lowerCD w).2:ℝ)) : ∀ w : List ℕ+, lowerWidth w = (lowerBeta-lowerAlpha)/((((lowerCD w).1:ℝ)*lowerAlpha+(lowerCD w).2)*(((lowerCD w).1:ℝ)*lowerBeta+(lowerCD w).2)) := by sorry
Source
Freiman report j_family.tex and j_certificates.tex, equal-three-width and lower-j3-uniform; exact source width-criterion route.