Four consecutive integers greater than are given. Prove that the sum of some three of the given numbers can be represented as the product of three distinct positive integers greater than .
Solution
Let , , , be the given numbers. The sum of the three smallest of them is , and the sum of the three largest numbers is . But at least one of the numbers and is even, that is, equal to the product of and , where . Therefore, this sum can be represented as the product of three distinct natural numbers: , , and .
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