Knight Time  
Brain Warmup 
Problem: 
What is the greatest number of chess knights you can place on a typical 8x8
chess board without any of them being in position to attack any other? The
graphic shows how knights can attack. More information about
chess knights can be found by clicking on the graphic.

Solvers: 

Solution: 
As you can see from the picture above a knight placed on a dark square can only attack light squares. Thus you can place a knight on every dark square and none of them will be able to attack each other. So the answer is at least 32 (the number of dark squares) knights. 
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