Let be a positive integer. We call a function a friend of if for at least one percent of positive integers such that the equation has a solution in positive integers such that . Let be a polynomial with non-negative real coefficients of total degree greater than such that , for all positive real numbers satisfying . Prove that would not be a friend of for all sufficiently large .
Solution
First, note that given the positive coefficients, if is the highest degree term appearing in , we have . Therefore, if and are in the specified region, we have:
Therefore, for some constant , we have , which implies that can have at most possibilities, which is a contradiction. ■
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