#include <bits/stdc++.h>
using namespace std;
const long long int INF = (1ll << 60) - 1;
long long int nCrModpDP(long long int n, long long int r, long long int p) {
  long long int i, j, C[r + 1];
  memset(C, 0, sizeof(C));
  C[0] = 1;
  for (i = 1; i <= n; i++) {
    for (j = min(i, r); j > 0; j--) {
      C[j] = (C[j] + C[j - 1]) % p;
    }
  }
  return C[r];
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long int tc = 1;
  while (tc--) {
    long long int fact[1001];
    fact[0] = fact[1] = 1;
    fact[2] = 2;
    fact[3] = 6;
    for (long long int i = 4; i < 1001; i++)
      fact[i] = ((fact[i - 1] % 1000000007) * (i % 1000000007)) % 1000000007;
    long long int n, m;
    cin >> n >> m;
    long long int ans = nCrModpDP(n + 2 * m - 1, n - 1, 1000000007);
    cout << ans % 1000000007;
  }
}
