#include<iostream> #include<vector> #include<algorithm> #include<functional> #include<queue> #include<stack> #include<set> #include<map> #include<unordered_map> #include<climits> #include<cstdlib> #include<cmath> #include<string> #include<iomanip> using namespace std; #define INF 1 << 29 #define LL long long int LL const MOD = 1000000007; int main(){ cin.tie(0); ios::sync_with_stdio(false); LL n; cin >> n; vector<vector<LL>> dp(n,vector<LL>(10,0)); for(int i = 0; i < 10; i++){ dp[n-1][i] = 1; } for(int i = n-2; i >= 0; i--){ for(int j = 0; j < 10; j++){ for(int k = 0; k <= j; k++){ dp[i][j] += dp[i+1][k]; dp[i][j] %= MOD; } } } LL ans = 0; for(int i = 0; i < 10; i++){ ans += dp[0][i]; ans %= MOD; } cout << ans << endl; return 0; }