#include <bits/stdc++.h>
using namespace std;
const long double pi = acos(-1.0);
const int day[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
const int digarr[10] = {6, 2, 5, 5, 4, 5, 6, 3, 7, 6};
const int dx[4] = {0, 1, 0, -1};
const int dy[4] = {1, 0, -1, 0};
const int dxo[8] = {-1, -1, -1, 0, 1, 1, 1, 0};
const int dyo[8] = {-1, 0, 1, 1, 1, 0, -1, -1};
const int alf = 26;
const int dig = 10;
const int two = 2;
const int th = 3;
const long long prost = 239;
const long long bt = 30;
const long double eps = 1e-9;
const long long INF = (long long)(1e18 + 239);
const int BIG = (int)(2e9 + 239);
const int MOD = 1e9 + 7;
const long long MOD2 = (long long)MOD * (long long)MOD;
mt19937_64 rnd(239);
const int M = (int)(2e5 + 239);
const int N = (int)(2e3 + 239);
const int L = 20;
const int T = (1 << 20);
const int B = (int)sqrt(M);
const int X = 4010;
int dp[two][X], n, c[X][X];
int32_t main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  for (int i = 0; i <= n; i++) c[i][0] = 1;
  for (int i = 1; i <= n; i++)
    for (int j = 1; j <= i; j++) {
      c[i][j] = c[i - 1][j] + c[i - 1][j - 1];
      if (c[i][j] >= MOD) c[i][j] -= MOD;
    }
  dp[0][0] = 1;
  dp[1][0] = 0;
  for (int k = 1; k <= n; k++) {
    for (int s = 0; s <= k - 1; s++) {
      dp[0][k] += 1LL * dp[0][k - 1 - s] * c[k - 1][s] % MOD;
      if (dp[0][k] >= MOD) dp[0][k] -= MOD;
      dp[1][k] += 1LL * dp[1][k - 1 - s] * c[k - 1][s] % MOD;
      if (dp[1][k] >= MOD) dp[1][k] -= MOD;
    }
    dp[1][k] += dp[0][k - 1];
    if (dp[1][k] >= MOD) dp[1][k] -= MOD;
    dp[1][k] += dp[1][k - 1];
    if (dp[1][k] >= MOD) dp[1][k] -= MOD;
  }
  cout << dp[1][n];
  return 0;
}
