136.--THE SULTAN'S ARMY.

A certain Sultan wished to send into battle an army that could be formed

into two perfect squares in twelve different ways. What is the smallest

number of men of which that army could be composed? To make it clear to

the novice, I will explain that if there were 130 men, they could be

formed into two squares in only two different ways--81 and 49, or 121

and 9. Of course, all the men must be used on every occasion.

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