#include <bits/stdc++.h>
using namespace std;
long long power(long long a, long long n) {
  a %= 1000000007;
  if (n == 1) return a;
  if (n == 0) return 1;
  if (n % 2)
    return (a * (power((a * a) % 1000000007, n / 2) % 1000000007)) % 1000000007;
  return power((a * a) % 1000000007, n / 2) % 1000000007;
}
const long long inf = (long long)1e18;
long long inverse(long long x) { return power(x, 1000000007 - 2) % 1000000007; }
long long fact[100000];
long long ncr(long long n, long long r) {
  long long ans = (fact[n - r] * fact[r]) % 1000000007;
  ans = inverse(ans);
  ans *= fact[n];
  ans %= 1000000007;
  return ans;
}
signed main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  ;
  long long n, m;
  cin >> n >> m;
  fact[0] = 1;
  for (long long i = 1; i < 100000; ++i)
    fact[i] = (fact[i - 1] * i) % 1000000007;
  cout << ncr(2 * m + n - 1, n - 1);
  return 0;
}
