Description: Given a function F on a well-ordered domain A there exists a subset of A such that F restricted to such subset is injective and onto the range of F (without using the axiom of choice). (Contributed by Glauco Siliprandi, 17-Aug-2020)
Ref | Expression | ||
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Hypotheses | wessf1ornlem.f | |
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wessf1ornlem.a | |
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wessf1ornlem.r | |
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wessf1ornlem.g | |
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Assertion | wessf1ornlem | |