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An 8 by 8 checkerboard has alternating black and white squares. How many distinct squares, with sides on the grid lines of the checkerboard (horizontal and vertical) and containing at least 4 black squares, can be drawn on the checkerboard?

https://latex.artofproblemsolving.com/8/7/a/87aa3c21435405d11d99ede53e0abc0dac7f4963.png

 Jun 4, 2020
 #1
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Using casework, the number of squares is 4*4 + 8*2 = 32.

 Jun 4, 2020
 #2
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I figured the answer out myself. It is 91. Thanks!

 Jun 5, 2020

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