I am so sorry for misleading you. I needed to solve this problem, because it occurred to me whilst I was solving another one. Indeed, what I had written is not true. In such case, could you help me find all integers for which

i divisible by

?

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- September 21st 2011, 09:15 AMgollumDivisibility
I am so sorry for misleading you. I needed to solve this problem, because it occurred to me whilst I was solving another one. Indeed, what I had written is not true. In such case, could you help me find all integers for which

i divisible by

? - September 21st 2011, 11:18 AMOpalgRe: Divisibility
- September 21st 2011, 11:25 AMHallsofIvyRe: Divisibility
It is impossible to prove something that is NOT true! What reason do you have to believe that this statement is true?

- September 21st 2011, 12:25 PMgollumRe: Divisibility
Hi! I have already corrected the post.

- September 21st 2011, 01:03 PMOpalgRe: Divisibility
You could try to show that the ratio increases towards a limiting value 4. The ratio is equal to 3 when n=1. For n>1, it will lie between 3 and 4, so can never again be an integer.

- September 21st 2011, 01:33 PMgollumRe: Divisibility
Thanks, but how do I find maximum and minimum of a function like this - I mean it is exponential as well as rational.

- September 22nd 2011, 12:40 AMOpalgRe: Divisibility
Probably the easiest approach is to write in the form . Then show that that fraction is positive and less than 1 when n>1.