// >>> TEMPLATES #include using namespace std; using ll = long long; using ld = long double; using i32 = int32_t; using i64 = int64_t; using u32 = uint32_t; using u64 = uint64_t; #define int ll #define double ld #define rep(i,n) for (int i = 0; i < (int)(n); i++) #define rep1(i,n) for (int i = 1; i <= (int)(n); i++) #define repR(i,n) for (int i = (int)(n)-1; i >= 0; i--) #define rep1R(i,n) for (int i = (int)(n); i >= 1; i--) #define loop(i,a,B) for (int i = a; i B; i++) #define loopR(i,a,B) for (int i = a; i B; i--) #define all(x) (x).begin(), (x).end() #define allR(x) (x).rbegin(), (x).rend() #define pb push_back #define eb emplace_back #define mp make_pair #define fst first #define snd second template auto constexpr inf = numeric_limits::max()/2-1; auto constexpr INF32 = inf; auto constexpr INF64 = inf; auto constexpr INF = inf; #ifdef LOCAL #include "debug.hpp" #else #define dump(...) (void)(0) #define say(x) (void)(0) #define debug if (0) #endif template using pque_max = priority_queue; template using pque_min = priority_queue, greater >; template ::value>::type> ostream& operator<<(ostream& os, T const& v) { bool f = true; for (auto const& x : v) os << (f ? "" : " ") << x, f = false; return os; } template ::value>::type> istream& operator>>(istream& is, T &v) { for (auto& x : v) is >> x; return is; } template ostream& operator<<(ostream& os, pair const& p) { return os << "(" << p.first << ", " << p.second << ")"; } template istream& operator>>(istream& is, pair& p) { return is >> p.first >> p.second; } struct IOSetup { IOSetup() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); } } iosetup; template struct FixPoint : private F { constexpr FixPoint(F&& f) : F(forward(f)) {} template constexpr auto operator()(T&&... x) const { return F::operator()(*this, forward(x)...); } }; struct MakeFixPoint { template constexpr auto operator|(F&& f) const { return FixPoint(forward(f)); } }; #define MFP MakeFixPoint()| #define def(name, ...) auto name = MFP [&](auto &&name, __VA_ARGS__) template struct vec_impl { using type = vector::type>; template static type make_v(size_t n, U&&... x) { return type(n, vec_impl::make_v(forward(x)...)); } }; template struct vec_impl { using type = T; static type make_v(T const& x = {}) { return x; } }; template using vec = typename vec_impl::type; template auto make_v(Args&&... args) { return vec_impl::make_v(forward(args)...); } template void quit(T const& x) { cout << x << endl; exit(0); } template constexpr bool chmin(T& x, U const& y) { if (x > y) { x = y; return true; } return false; } template constexpr bool chmax(T& x, U const& y) { if (x < y) { x = y; return true; } return false; } template constexpr auto sumof(It b, It e) { return accumulate(b,e,typename iterator_traits::value_type{}); } template int sz(T const& x) { return x.size(); } template int lbd(C const& v, T const& x) { return lower_bound(v.begin(), v.end(), x)-v.begin(); } template int ubd(C const& v, T const& x) { return upper_bound(v.begin(), v.end(), x)-v.begin(); } template int ppt(C const& v, F f) { return partition_point(v.begin(), v.end(), f)-v.begin(); } template struct Random { mt19937_64 mt{random_device{}()}; //mt19937_64 mt{(unsigned)time(0)}; Int a,b; // [a,b] Random(Int a, Int b) : a(a), b(b) {} Int operator()() { return uniform_int_distribution(a,b)(mt); } }; template Int rand(Int a, Int b) { // [a,b] static mt19937_64 mt{random_device{}()}; return uniform_int_distribution(a,b)(mt); } // <<< // >>> modint template class modint { static_assert(md < (1u<<31), ""); using M = modint; using i64 = int64_t; uint32_t x; public: static constexpr uint32_t mod = md; constexpr modint(i64 x = 0) : x((x%=md) < 0 ? x+md : x) { } constexpr i64 val() const { return x; } constexpr explicit operator i64() const { return x; } constexpr bool operator==(M r) const { return x == r.x; } constexpr bool operator!=(M r) const { return x != r.x; } constexpr M operator+() const { return *this; } constexpr M operator-() const { return M()-*this; } constexpr M& operator+=(M r) { x += r.x; x = (x < md ? x : x-md); return *this; } constexpr M& operator-=(M r) { x += md-r.x; x = (x < md ? x : x-md); return *this; } constexpr M& operator*=(M r) { x = (uint64_t(x)*r.x)%md; return *this; } constexpr M& operator/=(M r) { return *this *= r.inv(); } constexpr M operator+(M r) const { return M(*this) += r; } constexpr M operator-(M r) const { return M(*this) -= r; } constexpr M operator*(M r) const { return M(*this) *= r; } constexpr M operator/(M r) const { return M(*this) /= r; } friend constexpr M operator+(i64 x, M y) { return M(x)+y; } friend constexpr M operator-(i64 x, M y) { return M(x)-y; } friend constexpr M operator*(i64 x, M y) { return M(x)*y; } friend constexpr M operator/(i64 x, M y) { return M(x)/y; } constexpr M inv() const { assert(x > 0); return pow(md-2); } constexpr M pow(i64 n) const { n %= md-1; if (n < 0) n = (-n)*(md-2)%(md-1); M v = *this, r = 1; for (; n > 0; n >>= 1, v *= v) if (n&1) r *= v; return r; } #ifdef LOCAL friend string to_s(M r) { return to_s(r.val(), mod); } #endif friend ostream& operator<<(ostream& os, M r) { return os << r.val(); } friend istream& operator>>(istream& is, M &r) { i64 x; is >> x; r = x; return is; } }; // <<< //constexpr int64_t MOD = 998244353; constexpr int64_t MOD = 1e9+7; using mint = modint; // >>> mod table template struct ModTable { static constexpr int32_t Size = 1e6 + 10; static_assert(Size <= mod, ""); using ll = int64_t; int32_t fact[Size], finv[Size], inv[Size]; ModTable() { fact[0] = fact[1] = finv[0] = finv[1] = inv[1] = 1; for (int i = 2; i < Size; i++) { fact[i] = ll(fact[i-1])*i % mod; inv[i] = mod - ll(inv[mod%i])*(mod/i) % mod; finv[i] = ll(finv[i-1])*inv[i] % mod; } } }; const ModTable mod_tab; modint fact(int n) { assert(0 <= n); assert(n < ModTable::Size); return mod_tab.fact[n]; } modint finv(int n) { assert(0 <= n); assert(n < ModTable::Size); return mod_tab.finv[n]; } modint C(int n, int k) { if (n < 0 || k < 0 || n < k) return 0; return fact(n)*finv(k)*finv(n-k); } modint P(int n, int k) { assert(k >= 0); return fact(n)*finv(n-k); } modint sgn(int n) { return n%2 == 0 ? +1 : -1; } // <<< // >>> sieve namespace Sieve { constexpr int MAX = 2e6; vector ps, pf, mu; // primes, min prime factor, moebius auto sieve_init = [](){ pf.resize(MAX+1); iota(pf.begin(), pf.end(), 0); mu.resize(MAX+1,-1); mu[1] = 1; for (int i = 2; i <= MAX; ++i) { if (pf[i] == i) ps.push_back(i); for (int p : ps) { const int x = p*i; if (p > pf[i] || x > MAX) break; pf[x] = p; mu[x] = -mu[i]; if (i%p == 0) mu[x] = 0; } } return 0; }(); bool is_prime(int n) { assert(0 <= n); assert(n <= MAX); return pf[n] == n && n >= 2; } vector > prime_factor(int n) { assert(0 <= n); assert(n <= MAX); vector > ret; while (n > 1) { int p = pf[n], i = 0; while (pf[n] == p) ++i, n /= p; ret.emplace_back(p,i); } return ret; } vector divisors(int n) { assert(0 <= n); assert(n <= MAX); vector ret = {1}; for (auto p : prime_factor(n)) { int m = ret.size(); for (int i = 0; i < m; ++i) { for (int j = 0, v = 1; j < p.second; ++j) { v *= p.first; ret.push_back(ret[i]*v); } } } return ret; } } using namespace Sieve; // <<< int32_t main() { int n,k; cin >> n >> k; mint ans = 0; rep1 (i,n) if (i > 1 && n%i == 0 && k%i == 0) { ans += (-mu[i])*C(n/i,k/i); } cout << ans << endl; }