Consider the following equation:
where sign [a] represents the integer part of number a.
Let's find all integer z (z \gt 0), for which this equation is unsolvable in positive integers. The phrase "unsolvable in positive integers" means that there are no such positive integers x and y (x,y \gt 0), for which the given above equation holds.

Let's write out all such z in the increasing order: z1,z2,z3, and so on (zi \lt zi+1). Your task is: given the number n, find the number zn.

The first line contains a single integer n (1 \le n \le 40).

Print a single integer - the number zn modulo 1000000007 (109+7). It is guaranteed that the answer exists.