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You are not logged in. #1 20060803 16:38:55
Interesting identityProve that n is prime only and only when: Expand the divisors and sumofdivisors fuction as sums, which involve the floor function. Make a function that using floors finds the ith digit in the representation of n (for example demical representation) What is the connection between the sumofdigits function and the standard in the numberic theory ? Last edited by krassi_holmz (20060803 16:40:28) IPBLE: Increasing Performance By Lowering Expectations. #2 20060804 01:01:24
Re: Interesting identityMaybe I did my addition wrong, but: Edit: Now I'm confused about your wording. You have "only and only when". I took that as if and only if. But did you mean that if the sum is 1, then n is prime? In that case, 3 does not break your summation. "In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..." #3 20060804 02:04:03
Re: Interesting identity
3/2??? The function floor is always integer, so you can't get rational result. And yes, iff. Last edited by krassi_holmz (20060804 02:08:19) IPBLE: Increasing Performance By Lowering Expectations. #4 20060804 03:07:28
Re: Interesting identityAh!!! Floor. I saw it, but didn't think about it. That makes more sense now. "In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..." #5 20060804 03:09:45
Re: Interesting identityNot only that, krassi, but it appears that: Where gd is the great divisor of n other than n itself. Edit: Nevermind. It doesn't work as sum(8) = 3 Edit #2: Where did you find this, and do you have such a proof? If so, I'd like to see it. Otherwise, I'll try to help you on it. "In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..." #6 20060804 03:30:14
Re: Interesting identityIt's very simple. And yes, it has connection to the d(x) and many more NT functions Last edited by krassi_holmz (20060804 03:47:54) IPBLE: Increasing Performance By Lowering Expectations. #7 20060804 03:52:20
Re: Interesting identityIn general, Last edited by krassi_holmz (20060804 03:55:06) IPBLE: Increasing Performance By Lowering Expectations. #8 20060804 03:57:06
Re: Interesting identity,where sigma is the sum of the xth powers of all divisors of n. IPBLE: Increasing Performance By Lowering Expectations. 