#include<stdio.h>

int max(int a,int b)
{
	if(a>b)
		return a;
	return b;
}

int min(int a,int b)
{
	if(a<b)
		return a;
	return b;
}

long long int simplifica(int n,int f1,int f2)
{
	int i,j,fmax,fmin,start;
	long long int p=1;

	fmax=max(f1,f2);
	fmin=min(f1,f2);

	i=fmax+1;
	start=2;
	if(i==n)
		return n;

	while(i<=n)
	{
		for(j=start;j<=fmin;j++)
		{
			if(i%j==0)
			{
				p*=i/j;
				start=j+1;
				break;
			}
		}
		i++;
	}
	return p;
}
		
int main()
{
	int n,inc=0;
	long long int suma=0;
	FILE *f=fopen("nunta.in","r");
	fscanf(f,"%i",&n);
	fclose(f);

	for(;;)
	{
		n-=2;
		if(n<0)
			break;
		inc++;
		suma+=simplifica(n+inc,inc,n);
	}
	suma++;
	f=fopen("nunta.out","w");
	fprintf(f,"%lli\n",suma);
	fclose(f);
	return 0;
}