A derivation from boundary condition principles Author: Diego Luis Tentor Date: March 2026 Version: 1.0 — consolidated from Addenda A–E Status: §§2–5 derived · §6 structural reading + prediction · §7 proposed mechanism License: CC BY-SA 4.0 Abstract The periodic table organizes 118 known elements in a structure whose form — integer atomic numbers advancing in unit steps, period lengths…