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Everything about First uncountable ordinal
Smallest ordinal number that, considered as a set, is uncountable
In mathematics, the first uncountable ordinal, traditionally denoted by or sometimes by, is the smallest ordinal number that is the order type of an uncountable well-ordered set. It is the supremum of all countable ordinals. In the von Neumann representation, the elements of are the countable ordinals, of which there are uncountably many. Wikipedia →
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