#include <bits/stdc++.h>
using namespace std;
const long long P = 7 + 1e9;
long long ar[2005];
long long fn(long long b, long long p, long long m) {
  if (p == 0) return 1;
  if (p == 1) return b;
  long long x = fn(b, p / 2, m) % P;
  if (p % 2 == 0) return x * x % P;
  x = (fn(b, p - 1, m) % P * b) % P;
  return x;
}
long long ncr(long long n, long long r) {
  long long q = (ar[r] * ar[n - r]) % P;
  q = fn(q, P - 2, P);
  return ar[n] * q % P;
}
int main() {
  ar[0] = 1;
  for (long long i = 1; i < 2005; i++) ar[i] = (ar[i - 1] * i) % P;
  long long n, m;
  cin >> n >> m;
  long long ans = ncr(2 * m + n - 1, n - 1);
  cout << ans;
  return 0;
}
