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تسجيل مستخدم جديدThe topological pigeonhole principle for ordinals
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تأليف
Jacob Hilton
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Given a cardinal $kappa$ and a sequence $left(alpha_iright)_{iinkappa}$ of ordinals, we determine the least ordinal $beta$ (when one exists) such that the topological partition relation [betarightarrowleft(top,alpha_iright)^1_{iinkappa}] holds, including an independence result for one class of cases. Here the prefix $top$ means that the homogeneous set must have the correct topology rather than the correct order type. The answer is linked to the non-topological pigeonhole principle of Milner and Rado.
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