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I have the equation Y = FY (fixed point equation). How to get of it the equation for F through other combinator (in particular S- combinator with first fixed parameter)?

Paul Sweatte
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kvendingoldo
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  • This question is very unclear. What would "the equation for `F`" mean, for instance? – chi May 13 '15 at 19:35

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There's no way to do this -- consider the functions g and g ∘ g. Then Y(g) and Y(g ∘ g) are both g(g(g(g(g(...))))), so there's no way to go from Y(F) to F in general.

Lynn
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