View Code of Problem 73

#include<stdio.h>
int main()
{
	int N;
	scanf("%d",&N);
	int i;
	int a[1000];
	a[N] = 1;
	for(i=N;i>1;i--)
	{
		a[i-1] = (a[i]+1)*2;
		
	}
	printf("%d",a[1]);
	return 0;
}