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Eilenberg and Mac Lane in Categories for the Working Mathematician (p. 28) | Natural transformations

..."category" has been defined in order to be able to define "functor" and "functor" has been defined in order to be able to define "natural transformation."

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Algebra theory

Not to be confused with the general concept of algebra (abstract or otherwise), an algebra is an algebraic structure similar to a module, only with two internal binary operations.

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Algebraic geometry

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Category theory

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Functor categories	8:42 PM - October 07, 2025
Functors	8:12 PM - October 07, 2025
Kan extensions	11:12 AM - November 24, 2025
Natural transformations	8:38 PM - October 07, 2025
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The Salamander Lemma	3:38 PM - December 09, 2025
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Differential equations

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Representation theory

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Tropical algebraic geometry

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