View Code of Problem 73

#include<stdio.h>
int main()
{
	int x1,x0=1;
	int n;
	scanf("%d",&n);
	for(int i=0;i<n-1;i++)
	{
		x1=(x0+1)*2;
		x0=x1;
	}
	printf("%d",x1);
	return 0;
}