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by VyseofArcadia 3371 days ago
>{f ∈ [1..N ⟶ 1..N] : ∀ y ∈ 1..N : ∃ x ∈ 1..N : f[x]=y}

is not expert-level material.

1 comments

Didn't read the article, is that supposed to show the properties of a function that is both "1:1" and "onto"? Ie, the set of all inputs is the same as as the set of possible outputs, so for any x in the set, f(x) will return a result that is also in the set?

Didn't major or minor in mathematics but I took a few papers. Time to the read the article and collect my prize or look ignorant under my real name on the web.

EDIT: I was wrong! Though in my defense I had been given the context from TFA I think I would have got it.