#include <bits/stdc++.h>
using namespace std;

const int MOD = 1e9 + 7;

int main() {
  int H, W;
  cin >> H >> W;

  vector<int> f(H);
  for (int i = 1; i < H; ++i) f[i] = H - i;

  vector<int> g(W);
  for (int i = 1; i < W; ++i) g[i] = W - i;

  int n = max(H, W) + 1;
  f.resize(n);
  g.resize(n);

  auto convolve = [](vector<int> a) {
    vector<int> b = a;
    vector<int> np(a.size());
    for (int i = 2; i < a.size(); ++i) {
      if (np[i]) continue;
      for (int j = (a.size() - 1) / i; j; --j) {
        np[j * i] = 1;
        (b[j] += b[j * i]) %= MOD;
      }
    }
    return b;
  };

  auto inv_convolve = [](vector<int> a) {
    vector<int> b = a;
    vector<int> np(a.size());
    for (int i = 2; i < a.size(); ++i) {
      if (np[i]) continue;
      for (int j = 1; j * i < a.size(); ++j) {
        np[j * i] = 1;
        (b[j] -= b[j * i]) %= MOD;
      }
    }
    return b;
  };

  vector<int> cf = convolve(f);
  vector<int> cg = convolve(g);

  vector<int> cfg(n);
  for (int i = 1; i < n; ++i) {
    cfg[i] = 1LL * cf[i] * cg[i] % MOD;
  }

  vector<int> fg = inv_convolve(cfg);

  int ans = 2 * fg[1] % MOD;
  (ans += 1LL * W * (H - 1) % MOD) %= MOD;
  (ans += 1LL * H * (W - 1) % MOD) %= MOD;

  if (ans < 0) ans += MOD;
  cout << ans << endl;

  return 0;
}