# Help to prove this formula

1. May 16, 2006

### eljose

Hello i need help to prove the formula:

$$p_n =\sum_{k=2}^{2^{n}}[ |n/(1+ \pi (k))|^{1/n}]$$

where []=floor function and |x| the modulus of x...this appear in number theory to evaluate the n-th prime however i am not able to prove it....

Last edited: May 16, 2006
2. May 16, 2006

### HallsofIvy

Staff Emeritus
So according to this formula, with n= 3, 2 is the third prime? I did not know that!

3. May 16, 2006

### Curious3141

:rofl: Pure comedy!:rofl:

4. May 16, 2006

### Curious3141

Though in fact, that's 2^n at the top of the summation. Even then, something's wrong, I get the third prime as being three according to the summation. Need to check again since I rushed thru it, but it doesn't look right.