TITLE: Does anybody know of a site that has a set of all theorems?
QUESTION [2 upvotes]: I mean, if there exists a site that his function is to show and save theorems with their proofs?

REPLY [2 votes]: Here's a short list -- although it is indeed impossible to list all theorems.

Planetmath
ProofWiki
Metamath
Wikipedia
MathWorld

Feel free to add any website/reference you find!
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