#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll=long long;
using Graph=vector<vector<int>>;
#define MAX 2000005
#define MOD 1000000007
//#define MOD 998244353
#define INF 1000000000
//#define INF 1000000000000000000

int main(){
  ll A,B;
  cin>>A>>B;
  if(B>=A){
    //ans=(A+1)*(A+2)/2-4*A-3
    A%=MOD;
    ll ans=4*(A+1)*(A+2)/2%MOD+4*(MOD-A)+MOD-3;
    ans%=MOD;
    cout<<ans<<'\n';
  }else{
    ll ans=0;
    if(A%2!=B%2){
      ans+=2*B;
      A--;
    }
    ll a=(2*B+1)%MOD;

    ans+=a*(A%MOD)%MOD+(B+1)%MOD;
    ans%=MOD;
    cout<<ans<<'\n';
    return 0;
  }
}