#include <bits/stdc++.h>
using namespace std;
template <typename T, typename U>
inline void amin(T &a, U b) {
  a = (a > b ? b : a);
}
template <typename T, typename U>
inline void amax(T &a, U b) {
  a = (a > b ? a : b);
}
const int N = 2e3 + 5, mod = 1e9 + 7;
int64_t fac[N], inv[N];
long long int expo(long long int n, long long int p, long long int M) {
  long long int res = 1;
  while (p) {
    if (p & 1) res = (res * n) % M;
    n = (n * n) % M;
    p >>= 1;
  }
  return res;
}
void pre() {
  fac[0] = 1;
  inv[0] = 1;
  for (int i = 1; i < N; ++i) {
    fac[i] = fac[i - 1] * i;
    fac[i] %= mod;
    inv[i] = expo(fac[i], mod - 2, mod);
  }
}
int64_t nck(int n, int k) { return (fac[n] * inv[n - k] % mod * inv[k] % mod); }
void solve() {
  int n, m;
  cin >> n >> m;
  cout << nck(n + 2 * m - 1, n - 1) << '\n';
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int t = 1;
  pre();
  while (t--) {
    solve();
  }
}
