Found 4 comments on HN
taeric · 2016-09-28 · Original thread
There are full books on these called "Proofs Without Words". On my wishlist. :)
jgg · 2010-07-01 · Original thread
If you like this sort of thing, definitely check out this book:
screwperman · 2009-07-25 · Original thread
If you like this, you'll love the book Proofs without Words: Exercises in Visual Thinking:
Nate · 2007-10-10 · Original thread
If you really like visual mathematics, then there is a book called "Proofs without words":

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