#include #include using namespace std; typedef long long ll; int used[3000010]; ll ans = 0,mod = 1000000007,h,w; ll inv = (mod + 1)/2; void solve(int x){ int y = x; vector fac; while(y!=1){ int k = used[y]; fac.push_back(k); while(y%k==0 && y!=1){ y /= k; } } int i,j,s = fac.size(); ll num = 0,sum = 0; for(i=0;i<(1<> h >> w; for(i=1;i<=3000000;i++){ used[i] = -1; } used[1] = 1; for(i=2;i<=h;i++){ for(j=i;j<=h;j+=i){ if(used[j]==-1) used[j] = i; } } for(i=1;i<=h;i++){ solve(i); } ans *= 2; (ans += h*(w - 1)%mod + w*(h - 1)%mod) %= mod; cout << ans << endl; }