User:Bxiao31415
AOPS Contributions
Observe that if such that n is a solution to the desired equation, so is , where m is an integer, . \\So we only need to consider n from 1 to 60. As shown in Solution 2, there are 4 cases which we will split into 2 main cases: \\ \\Case 1: or , \\Case 2: or , \\There are 4 values of n where satisfying or . \\ \\I claim that there are 4 values of satisfying Case 1. Suppose x is one value of n satisfying or , and . \\Hence the solutions satisfying or , are of the form , so the values of are (mod 5), so (mod 5) and hence the value of m is unique since to satisfy and 2 and 5 are relatively prime. \\ \\A similar approach can be used to show the same for Case 2, that there are 4 values of . \\ \\Hence our answer is .