int n,m;
int binomialCoeff(int n, int r)
{

    if (r > n)
        return 0;
    long long int m = 1000000007;
    long long int inv[r + 1] = { 0 };
    inv[0] = 1;
    if(r+1>=2)
    inv[1] = 1;

    for (int i = 2; i <= r; i++) {
        inv[i] = m - (m / i) * inv[m % i] % m;
    }

    int ans = 1;
    for (int i = 2; i <= r; i++) {
        ans = ((ans % m) * (inv[i] % m)) % m;
    }
    for (int i = n; i >= (n - r + 1); i--) {
        ans = ((ans % m) * (i % m)) % m;
    }
    return ans;
}


signed main()
{
    fast
    cin>>n>>m;

    cout<<binomialCoeff(n+2*m-1,2*m)<<endl;;

  return 0;
}