An explicit ten-color certificate for the van der Waerden lower bound W(10,3) > 938

This dataset contains an explicit coloring of the integers 1 through 938 with ten colors. The certificate is a 938-character string over a–j; its character at position i gives the color of integer i. No three integers x, x + d, and x + 2d, with d > 0, have the same color. It therefore certifies W(10,3) > 938, where the first argument counts colors and the second gives the progression length. IRSI’s research note W(10,3) > 937, dated 13 October 2026, reports 937-position certificates. The present coloring advances that documented bound by one position. The first 937 characters of this coloring differ at exactly 33 positions from IRSI’s 937-position certificate B, W_10_3_gt_937_b.txt.The SHA-256 of the linked file is a8b13f39d0cb9aae3a2735f6c4504e51fde4eb8514400ac4c983a124d7c2ce0dThe uploaded files include the text certificate, two independently written verifiers, a SHA-256 manifest, and an exact grid visualization. Running both verifiers reports zero monochromatic three-term progressions; one checks all 219,492 such progressions in the interval. According to the local search log, the AI-assisted search first recorded a zero-conflict coloring at 2026-11-01 05:30:29.891 UTC. This local finding time is distinct from the later public Zenodo publication time.