卡特兰数

import java.math.BigInteger;
import java.util.Scanner;


public class Main {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input = new Scanner(System.in);
        BigInteger []k = new BigInteger[1100];
        k[0] = BigInteger.valueOf(1);
        for(int j=1;j<110;j++)
        {
                k[j]=k[j-1].multiply(BigInteger.valueOf(4*j-2)).divide(BigInteger.valueOf(j+1));  
        }
        while (input.hasNext())  
        {  
            int times=input.nextInt();  
            if(times!=-1)  
                System.out.println(k[times]);  
            else 
            {  
                break;  
            }  
        }  
    }

}