Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.
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Claim. Galvin and Larson's Theorem 9 reads: "If and , then, either , or else for some ." In the reading of Problem 592 (its Formulation), it follows that for every decomposable with , so no such has the property, and that the question reduces to the exponents . The proof combines the paper's Theorem 3, that can be pinned to whenever is decomposable and (proved through Lemmas 4--6, Lemma 4 being Specker's), with Specker's and his observation that a partition relation passes along a pinning map. Theorem 2 of the paper adds the converse, that cannot be pinned to when is indecomposable (Theorem 8), so pinning gives no negative relation at the exponents left open. The paper is F. Galvin and J. Larson, Pinning countable ordinals, Fund. Math. 82 (1974/75), no. 4, 357--361, DOI 10.4064/fm-82-4-357-361, the site's [GaLa74], received 10 September 1973; the publisher's record gives the year 1975 and no month or day, so the page name carries 1 January 1975. The paper is filed with a transcription on the library's source card.
Covers. Every decomposable exponent with : the property fails. This contains Specker's finite . Not covered: the exponents and the indecomposable , among them Chang's and the cases that Schipperus decides.
Depends on. Specker's relation and the transfer of partition relations along pinning maps, which the paper's proof of Theorem 9 cites.
Acceptance. Refereed: the paper appeared in Fundamenta Mathematicae,
volume 82. The site labels the problem OPEN, and its commentary crediting
Galvin and Larson on an open problem is not an acceptance, so no reviewed
evidence is listed.