#include using namespace std; using int64 = long long; const int mod = (int) (1e9 + 7); const int64 infll = (1LL << 62) - 1; const int inf = (1 << 30) - 1; struct IoSetup { IoSetup() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(10); cerr << fixed << setprecision(10); } } iosetup; template< typename T1, typename T2 > ostream &operator<<(ostream &os, const pair< T1, T2 > &p) { os << p.first << " " << p.second; return os; } template< typename T1, typename T2 > istream &operator>>(istream &is, pair< T1, T2 > &p) { is >> p.first >> p.second; return is; } template< typename T > ostream &operator<<(ostream &os, const vector< T > &v) { for(int i = 0; i < (int) v.size(); i++) { os << v[i] << (i + 1 != v.size() ? " " : ""); } return os; } template< typename T > istream &operator>>(istream &is, vector< T > &v) { for(T &in : v) is >> in; return is; } template< typename T1, typename T2 > inline bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); } template< typename T1, typename T2 > inline bool chmin(T1 &a, T2 b) { return a > b && (a = b, true); } template< typename T = int64 > vector< T > make_v(size_t a) { return vector< T >(a); } template< typename T, typename... Ts > auto make_v(size_t a, Ts... ts) { return vector< decltype(make_v< T >(ts...)) >(a, make_v< T >(ts...)); } template< typename T, typename V > typename enable_if< is_class< T >::value == 0 >::type fill_v(T &t, const V &v) { t = v; } template< typename T, typename V > typename enable_if< is_class< T >::value != 0 >::type fill_v(T &t, const V &v) { for(auto &e : t) fill_v(e, v); } template< typename F > struct FixPoint : F { FixPoint(F &&f) : F(forward< F >(f)) {} template< typename... Args > decltype(auto) operator()(Args &&... args) const { return F::operator()(*this, forward< Args >(args)...); } }; template< typename F > inline decltype(auto) MFP(F &&f) { return FixPoint< F >{forward< F >(f)}; } template< int mod > struct ModInt { int x; ModInt() : x(0) {} ModInt(int64_t y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {} ModInt &operator+=(const ModInt &p) { if((x += p.x) >= mod) x -= mod; return *this; } ModInt &operator-=(const ModInt &p) { if((x += mod - p.x) >= mod) x -= mod; return *this; } ModInt &operator*=(const ModInt &p) { x = (int) (1LL * x * p.x % mod); return *this; } ModInt &operator/=(const ModInt &p) { *this *= p.inverse(); return *this; } ModInt operator-() const { return ModInt(-x); } ModInt operator+(const ModInt &p) const { return ModInt(*this) += p; } ModInt operator-(const ModInt &p) const { return ModInt(*this) -= p; } ModInt operator*(const ModInt &p) const { return ModInt(*this) *= p; } ModInt operator/(const ModInt &p) const { return ModInt(*this) /= p; } bool operator==(const ModInt &p) const { return x == p.x; } bool operator!=(const ModInt &p) const { return x != p.x; } ModInt inverse() const { int a = x, b = mod, u = 1, v = 0, t; while(b > 0) { t = a / b; swap(a -= t * b, b); swap(u -= t * v, v); } return ModInt(u); } ModInt pow(int64_t n) const { ModInt ret(1), mul(x); while(n > 0) { if(n & 1) ret *= mul; mul *= mul; n >>= 1; } return ret; } friend ostream &operator<<(ostream &os, const ModInt &p) { return os << p.x; } friend istream &operator>>(istream &is, ModInt &a) { int64_t t; is >> t; a = ModInt< mod >(t); return (is); } }; using modint = ModInt< mod >; vector< bool > isprime; vector< int > primes; void sieve(int n) { if((int) isprime.size() >= n + 1) return; isprime.assign(n + 1, true); isprime[0] = isprime[1] = false; int sqrtn = (int) (sqrt(n * 1.) + .5); for(int i = 2; i <= sqrtn; i++) if(isprime[i]) { for(int j = i * i; j <= n; j += i) isprime[j] = false; } primes.clear(); for(int i = 2; i <= n; i++) if(isprime[i]) primes.push_back(i); } vector< int > mobiusMu; void calcMobiusMu() { int n = (int) isprime.size() - 1; mobiusMu.assign(n + 1, 1); for(int i = 2; i <= n; i++) if(isprime[i]) { if((int64) i * i <= n) { for(int j = i * i; j <= n; j += i * i) mobiusMu[j] = 0; } for(int j = i; j <= n; j += i) mobiusMu[j] *= -1; } } // https://oeis.org/A115009 int main() { sieve(3000000); calcMobiusMu(); int64 H, W; cin >> H >> W; --H, --W; const int MAX_N = 3000000; vector< modint > dp(MAX_N); for(int i = 1; i <= W; i++) { dp[i] = W - i + 1; } for(int i = 1; i <= MAX_N; i++) { for(int j = i + i; j <= MAX_N; j += i) { dp[i] += dp[j]; } } vector< modint > ans(H + 1); for(int i = 1; i <= H; i++) { dp[i] *= mobiusMu[i]; for(int j = i; j <= H; j += i) { ans[j] += dp[i]; } } modint ret = 0; for(int i = 1; i <= H; i++) { ret += ans[i] * (H - i + 1); } cout << ret * 2 + 2 * H * W + H + W << endl; }