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Everything about Subcountability
Mathematical property of sets
In constructive mathematics, a collection is subcountable if there exists a partial surjection from the natural numbers onto it. This may be expressed as where denotes that is a surjective function from onto. The surjection is a member of and here the subclass of is required to be a set. In other words, all elements of a subcountable collection are functionally in the image of an indexing set of counting numbers and thus the set can be understood as being dominated by the countable set. Wikipedia →
🧠Start here: a 6-step reading path
- Read the overview: SubcountabilityA 5-minute orientation
- Pick up a classic book: PewDiePie MalbuchThe most-reprinted book on the subject
- Read the landmark paper: Subcountability under realizability.Cited 6 times
- Go sideways: Constructive set theoryA closely related topic
- Go sideways: Reverse mathematicsA closely related topic
đź“– Definitions
Noun The property of being subcountable.
🗂️ The subject at a glance
🏆 Landmark papers (most cited)
đź“š Books worth reading
- 📕PewDiePie MalbuchHelle Färbung · 2019
- 📕PewDiePie KleurboekHeldere Kleuren · 2019
- 📕PewDiePie Coloring BookBright Coloring · 2019
- 📕PewDiePie Libro Da ColorareColorazione Brillante · 2019
Ranked by number of editions on Open Library, a rough measure of how lasting a book is.
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