Notes on verification

Directly confirmed by Wikipedia's Timeline of Mathematics and History of mathematical notation articles, with additional corroboration from an academic paper and a secondary wiki source. Terminology and description are consistent across all sources. [tier=unverified indep_score=0.3 clusters=2 claim_tier=notable] [rescored 2026-09-15: curated origin-host map (PR #65); unclassified hosts no longer scored as aggregators]