defn: Left Kan extensions of corepresentables are corepresentable#628
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aathn wants to merge 2 commits into
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defn: Left Kan extensions of corepresentables are corepresentable#628aathn wants to merge 2 commits into
aathn wants to merge 2 commits into
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ncfavier
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Apr 30, 2026
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I guess a higher-level proof would be that よ(Fc) and Lan_F よ(c) both represent the same functor, since [C, Set](Lan_F よ(c), H) ≅ [C, Set](よ(c), HF) ≅ HF(c) ≅ [C, Set](よ(Fc), H).
This is fine though.
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Description
Proves that the left Kan extension of a corepresentable functor is again corepresentable. I'm not sure whether this result is easily derivable using some abstract machinery already in place; if so, please let me know.
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