Four-Squares
2² ends in a 4
12² ends with 44
Find a square that ends with 444.
Find another that ends with 4444.
2^2 ends in a 4.
12^2 ends with 44.
Find a square that ends with 444.
One that ends with 4444?
— James Tanton (@jamestanton) March 13, 2014
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