# Verification report

**Result:** Complete proof of the specified-position duplicate-leaf
parse-word assertion, using the established four-color theorem. The
source is OWR-4425-011 and Cooper--Rowland--Zeilberger Conjecture 19.

**Proof:** Two interval triangulations are glued on a sphere. The shared
uncle/nephew condition gives a vertex with at most four distinct
neighbors, whose two specified boundary neighbors are nonadjacent.
Contract their length-two path, four-color the planar minor, split them,
and restore the center with an unused color. Nonzero F_2^2 edge
differences give both valid parse trees and the required equal letters.

**Logical scope:** A common-padding construction gives the reverse
implication to unrestricted common parsing. Using the established
equivalence, the conjecture has four-color-theorem strength. No new
proof of that theorem or four-color-free inductive reduction is claimed.

**Exact finite diagnostics:** 102,039 unordered tree pairs with repetition
for 3<=n<=8, including 67,460 eligible positions, all pass. Explicit
minor-coloring lifts are checked in 6,014 cases with n<=7; 64,976 grammar
words are compared with interval-edge colorings. Normal and optimized
Python outputs agree. Only the standard library is needed. These checks
do not replace the general proof.

**Source audit:** Full relevant original pages and Conjecture 19 were
visually inspected. The special-class literature is credited. The
four-color theorem is used as an established result, not independently
reverified here. The bounded search does not certify novelty or priority.

**Review:** Originating-researcher self-audit completed. No external
reviewer or proof-assistant formalization is claimed. AI assistance is
disclosed in prose. Author: Alper Ferudun, Mercury Software GmbH.

**Package:** Four pages visually inspected and desktop compilation
successful. The manifest records source hashes, portable build, exact
replay, and upload hashes. Third-party PDFs are not in the public ZIP.