import java.math.*;

 import java.util.Scanner;

 public class Main {

     public static void main(String[] args) {

         Scanner in1 = new Scanner(System.in);

         BigInteger h[] = new BigInteger[105];

         int i,n;

         h[0]=BigInteger.ONE;

         for(i=1;i<=100;i++) {

             h[i]=h[i-1].multiply(BigInteger.valueOf(4*i-2)).divide(BigInteger.valueOf(i+1));

         }

         while(in1.hasNext()) {

             n=in1.nextInt();

             if(n==-1)break;

             System.out.println(h[n]);

         }

     }

 }