#include <bits/stdc++.h>
using namespace std;
const long long mod = 1e9 + 7;
const long long mod1 = 998244353;
long long power(long long a, long long b) {
  long long res = 1;
  while (b > 0) {
    if (b % 2 == 1) {
      res = (res * a) % mod;
    }
    a = (a * a) % mod;
    b >>= 1;
  }
  return res;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int t;
  t = 1;
  long long lookup[1001][11];
  for (int i = 0; i < 1001; i++) {
    for (int j = 0; j < 11; j++) {
      lookup[i][j] = 0;
    }
  }
  lookup[0][0] = 0;
  for (int i = 1; i <= 10; i++) {
    lookup[1][i] = 1;
    lookup[0][i] = 1;
  }
  for (int i = 1; i <= 1000; i++) {
    lookup[i][1] = i;
    lookup[i][0] = 1;
  }
  for (int i = 2; i <= 1000; i++) {
    for (int j = 2; j <= 10; j++) {
      lookup[i][j] += lookup[i - 1][j] + lookup[i][j - 1];
      lookup[i][j] %= mod;
    }
  }
  while (t--) {
    int n, m;
    cin >> n >> m;
    long long ans = 0;
    long long temp1, temp2, temp3;
    for (int i = 1; i <= n; i++) {
      temp1 = n - i + 1;
      temp1 = lookup[temp1][m];
      temp2 = i;
      temp2 = lookup[temp2][m - 1];
      temp3 = (temp1 * temp2) % mod;
      ans += temp3;
      ans %= mod;
    }
    cout << ans;
  }
}
