#include <bits/stdc++.h>
#define _GLIBCXX_DEBUG
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rep2(i, s, n) for (int i = s; i < (int)(n); i++)
#define Clear(a) a = decltype(a)()
#define all(a) a.begin(),a.end()
typedef long long ll;
typedef pair<int,int> p;
//const ll big=998244353;
const ll big=1000000007;
const int dx[4]={1,0,-1,0};
const int dy[4]={0,1,0,-1};
ll max(ll x,ll y){
if(x>y)return x;
else return y;
}
ll min(ll x,ll y){
if(x<y)return x;
else return y;
}
ll expm(ll x,ll y){
    if(y==0)return 1;//0^0=1
    if(x==1||x==0)return x;
    if(y%2==1)return (expm(x,y-1)*x)%big;
    ll t=expm(x,y/2);
    return (t*t)%big;
}
ll exp(ll x,ll y){
    if(y==0)return 1;//0^0=1
    if(x==1||y==0)return x;
    if(y%2==1)return exp(x,y-1)*x;
    ll t=exp(x,y/2);
    return t*t;
}
ll inv(ll x){
    return expm(x,big-2);
}


int main(){
    ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    cout << fixed << setprecision(10);
    /*--------------------------------*/

    ll m,n;cin >> n >> m;
    vector<ll> fac(m+1),facin(m+1);
    fac[0]=1;
    facin[0]=1;
    rep(i,m){
        fac[i+1]=fac[i]*(i+1)%big;
        facin[i+1]=facin[i]*inv(i+1)%big;
    }
    ll ans=0;
    rep2(i,n,m+1){//com(i,n)
        ans+=fac[i]*facin[n]%big *facin[i-n]%big;
        ans%=big;
    }
    cout << ans << endl;
}