#include<iostream>
#include<string>
#include<algorithm>
#include <cstdio>
#include <cstring>using namespace std;#define MAXN 9999
#define DLEN 4class BigNum
{
private:int a[50];    //可以控制大数的位数int len;       //大数长度
public:BigNum(){ len = 1; memset(a,0,sizeof(a)); }   //构造函数BigNum(const int);       //将一个int类型的变量转化为大数BigNum(const BigNum &);  //拷贝构造函数BigNum &operator=(const BigNum &);   //重载赋值运算符，大数之间进行赋值运算
friend ostream& operator<<(ostream&,  BigNum&);   //重载输出运算符
BigNum operator+(const BigNum &) const;   //重载加法运算符，两个大数之间的相加运算BigNum operator*(const BigNum &) const;   //重载乘法运算符，两个大数之间的相乘运算bool   operator>(const int & t)const;      //大数和一个int类型的变量的大小比较bool   operator>(const BigNum & T)const;   //大数和另一个大数的大小比较
};BigNum dp[220][220];BigNum d(int x, int y) {if(x == y) return 1;if(x > y) return 1;if(dp[x][y] > 0) return dp[x][y];if(y - x == 1) return (dp[x][y] = 1);BigNum ans = 0;for(int i = x+1; i <= y; i +=2) {ans = ans + d(x+1, i-1)*d(i+1, y);}return (dp[x][y] = ans);
}int main(){int n;while(scanf("%d", &n) == 1 && n != -1) {BigNum ans = d(1, 2*n);cout << ans << endl;}return 0;
}BigNum::BigNum(const int b)     //将一个int类型的变量转化为大数
{int c,d = b;len = 0;memset(a,0,sizeof(a));while(d > MAXN){c = d - (d / (MAXN + 1)) * (MAXN + 1);d = d / (MAXN + 1);a[len++] = c;}a[len++] = d;
}
BigNum::BigNum(const BigNum & T) : len(T.len)  //拷贝构造函数
{int i;memset(a,0,sizeof(a));for(i = 0 ; i < len ; i++)a[i] = T.a[i];
}
BigNum & BigNum::operator=(const BigNum & n)   //重载赋值运算符，大数之间进行赋值运算
{int i;len = n.len;memset(a,0,sizeof(a));for(i = 0 ; i < len ; i++)a[i] = n.a[i];return *this;
}ostream& operator<<(ostream& out,  BigNum& b)   //重载输出运算符
{int i;cout << b.a[b.len - 1];for(i = b.len - 2 ; i >= 0 ; i--){cout.width(DLEN);cout.fill('0');cout << b.a[i];}return out;
}BigNum BigNum::operator+(const BigNum & T) const   //两个大数之间的相加运算
{BigNum t(*this);int i,big;      //位数big = T.len > len ? T.len : len;for(i = 0 ; i < big ; i++){t.a[i] +=T.a[i];if(t.a[i] > MAXN){t.a[i + 1]++;t.a[i] -=MAXN+1;}}if(t.a[big] != 0)t.len = big + 1;elset.len = big;return t;
}BigNum BigNum::operator*(const BigNum & T) const   //两个大数之间的相乘运算
{BigNum ret;int i,j,up;int temp,temp1;for(i = 0 ; i < len ; i++){up = 0;for(j = 0 ; j < T.len ; j++){temp = a[i] * T.a[j] + ret.a[i + j] + up;if(temp > MAXN){temp1 = temp - temp / (MAXN + 1) * (MAXN + 1);up = temp / (MAXN + 1);ret.a[i + j] = temp1;}else{up = 0;ret.a[i + j] = temp;}}if(up != 0)ret.a[i + j] = up;}ret.len = i + j;while(ret.a[ret.len - 1] == 0 && ret.len > 1)ret.len--;return ret;
}
bool BigNum::operator >(const int & t) const    //大数和一个int类型的变量的大小比较
{BigNum b(t);return *this>b;
}bool BigNum::operator>(const BigNum & T) const   //大数和另一个大数的大小比较
{int ln;if(len > T.len)return true;else if(len == T.len){ln = len - 1;while(a[ln] == T.a[ln] && ln >= 0)ln--;if(ln >= 0 && a[ln] > T.a[ln])return true;elsereturn false;}elsereturn false;
}