Proving Sum of Reciprocal of Natural Numbers is Not an Integer

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The discussion focuses on proving that the sum of the reciprocals of natural numbers, \sum_1^n\frac{1}{k}, is not an integer for n greater than 1. Participants explore various approaches, including bounding the sum with integrals, but find these methods insufficient. A specific formula is mentioned, \sum_1^n\frac{1}{k}=\frac{(n-1)!+n(n-2)!+n(n-1)(n-3)!+...+n!}{n!}, yet a contradiction remains elusive. A reference to an older thread suggests that a hint provided there may assist in resolving the issue. The conversation highlights the complexity of the problem and the need for a more effective proof strategy.
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How do I show that \sum_1^n\frac{1}{k} is not an integer for n>1? I tried bounding them between two integrals but that doesn't cut it. I know that \sum_1^n\frac{1}{k}=\frac{(n-1)!+n(n-2)!+n(n-1)(n-3)!+...+n!}{n!} but I can't get a contradiction.
 
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