Freiman lower construction: entry context B
ProvedFreiman.lower_entry_context_Bfreimanlower-construction
Finite terminal suffix and parity classification for family B, with the exact H endpoint formula. B at k=0 and auxiliary B are the odd terminal2,3 exception.
Preamble
import Definitions.Def_Freiman_lowerInitialEntry import Definitions.Def_Freiman_lowerCertificates import Mathlib.Tactic.Linarith import Mathlib.Tactic.Push open Freiman
Formal statement
theorem Freiman.lower_entry_context_B (n k p : ℕ) : ∃ c : LowerEntryClass,
lowerEntryContext c (lowerNormalize (lowerFamilyPair .B n k p)) ∧
lowerFamilyH .B n k p = lowerEntryH c (lowerNormalize (lowerFamilyPair .B n k p)) := by
sorrySource
Freiman's Hall ray: Proof report and corrected English text (8 September 2026), parts/lower_core.tex, prop:lc-H-entry; source H certificate appendix