#include using namespace std; using lint = long long; template using V = vector; template using VV = V< V >; template struct ModInt { using M = ModInt; unsigned v; constexpr ModInt() : v(0) {} constexpr ModInt(auto x) : v(x >= 0 ? x % P : (P - -x % P) % P) {} constexpr ModInt(unsigned v, int) : v(v) {} static constexpr unsigned p() { return P; } M operator+() const { return *this; } M operator-() const { return {v ? P - v : 0, 0}; } explicit operator bool() const noexcept { return v; } bool operator!() const noexcept { return !(bool)*this; } M operator*(M r) const { return M(*this) *= r; } M operator/(M r) const { return M(*this) /= r; } M operator+(M r) const { return M(*this) += r; } M operator-(M r) const { return M(*this) -= r; } bool operator==(M r) const { return v == r.v; } bool operator!=(M r) const { return !(*this == r); } M& operator*=(M r) { v = (uint64_t)v * r.v % P; return *this; } M& operator/=(M r) { return *this *= r.inv(); } M& operator+=(M r) { if ((v += r.v) >= P) v -= P; return *this; } M& operator-=(M r) { if ((v += P - r.v) >= P) v -= P; return *this; } M inv() const { int a = v, b = P, x = 1, u = 0; while (b) { int q = a / b; swap(a -= q * b, b); swap(x -= q * u, u); } assert(a == 1); return x; } M pow(auto n) const { if (n < 0) return pow(-n).inv(); M res = 1; for (M a = *this; n; a *= a, n >>= 1) if (n & 1) res *= a; return res; } friend M operator*(auto l, M r) { return M(l) *= r; } friend M operator/(auto l, M r) { return M(l) /= r; } friend M operator+(auto l, M r) { return M(l) += r; } friend M operator-(auto l, M r) { return M(l) -= r; } friend ostream& operator<<(ostream& os, M r) { return os << r.v; } friend istream& operator>>(istream& is, M& r) { lint x; is >> x; r = x; return is; } friend bool operator==(auto l, M r) { return M(l) == r; } friend bool operator!=(auto l, M r) { return !(l == r); } }; using Mint = ModInt<(unsigned)1e9 + 7>; int main() { cin.tie(nullptr); ios::sync_with_stdio(false); lint h, w; cin >> h >> w; V dp(min(h, w)); for (lint d = min(h, w) - 1; d; --d) { lint x = (w - 1) / d, y = (h - 1) / d; dp[d] = Mint(w * x - d * x * (x + 1) / 2) * Mint(h * y - d * y * (y + 1) / 2); for (int m = 2 * d; m < min(h, w); m += d) { dp[d] -= dp[m]; } } Mint res = h * (w - 1) + w * (h - 1); if (1 < min(h, w)) res += 2 * dp[1]; cout << res << '\n'; }