#include using i64 = long long; template constexpr T power(T a, i64 b) { T res = 1; for (; b; b /= 2, a *= a) { if (b % 2) { res *= a; } } return res; } constexpr i64 mul(i64 a, i64 b, i64 p) { i64 res = a * b - i64(1.L * a * b / p) * p; res %= p; if (res < 0) { res += p; } return res; } template struct MLong { i64 x; constexpr MLong() : x{} {} constexpr MLong(i64 x) : x{norm(x % getMod())} {} static i64 Mod; constexpr static i64 getMod() { if (P > 0) { return P; } else { return Mod; } } constexpr static void setMod(i64 Mod_) { Mod = Mod_; } constexpr i64 norm(i64 x) const { if (x < 0) { x += getMod(); } if (x >= getMod()) { x -= getMod(); } return x; } constexpr i64 val() const { return x; } explicit constexpr operator i64() const { return x; } constexpr MLong operator-() const { MLong res; res.x = norm(getMod() - x); return res; } constexpr MLong inv() const { assert(x != 0); return power(*this, getMod() - 2); } constexpr MLong &operator*=(MLong rhs) & { x = mul(x, rhs.x, getMod()); return *this; } constexpr MLong &operator+=(MLong rhs) & { x = norm(x + rhs.x); return *this; } constexpr MLong &operator-=(MLong rhs) & { x = norm(x - rhs.x); return *this; } constexpr MLong &operator/=(MLong rhs) & { return *this *= rhs.inv(); } friend constexpr MLong operator*(MLong lhs, MLong rhs) { MLong res = lhs; res *= rhs; return res; } friend constexpr MLong operator+(MLong lhs, MLong rhs) { MLong res = lhs; res += rhs; return res; } friend constexpr MLong operator-(MLong lhs, MLong rhs) { MLong res = lhs; res -= rhs; return res; } friend constexpr MLong operator/(MLong lhs, MLong rhs) { MLong res = lhs; res /= rhs; return res; } friend constexpr std::istream &operator>>(std::istream &is, MLong &a) { i64 v; is >> v; a = MLong(v); return is; } friend constexpr std::ostream &operator<<(std::ostream &os, const MLong &a) { return os << a.val(); } friend constexpr bool operator==(MLong lhs, MLong rhs) { return lhs.val() == rhs.val(); } friend constexpr bool operator!=(MLong lhs, MLong rhs) { return lhs.val() != rhs.val(); } }; template<> i64 MLong<0LL>::Mod = 1; template struct MInt { int x; constexpr MInt() : x{} {} constexpr MInt(i64 x) : x{norm(x % getMod())} {} static int Mod; constexpr static int getMod() { if (P > 0) { return P; } else { return Mod; } } constexpr static void setMod(int Mod_) { Mod = Mod_; } constexpr int norm(int x) const { if (x < 0) { x += getMod(); } if (x >= getMod()) { x -= getMod(); } return x; } constexpr int val() const { return x; } explicit constexpr operator int() const { return x; } constexpr MInt operator-() const { MInt res; res.x = norm(getMod() - x); return res; } constexpr MInt inv() const { assert(x != 0); return power(*this, getMod() - 2); } constexpr MInt &operator*=(MInt rhs) & { x = 1LL * x * rhs.x % getMod(); return *this; } constexpr MInt &operator+=(MInt rhs) & { x = norm(x + rhs.x); return *this; } constexpr MInt &operator-=(MInt rhs) & { x = norm(x - rhs.x); return *this; } constexpr MInt &operator/=(MInt rhs) & { return *this *= rhs.inv(); } friend constexpr MInt operator*(MInt lhs, MInt rhs) { MInt res = lhs; res *= rhs; return res; } friend constexpr MInt operator+(MInt lhs, MInt rhs) { MInt res = lhs; res += rhs; return res; } friend constexpr MInt operator-(MInt lhs, MInt rhs) { MInt res = lhs; res -= rhs; return res; } friend constexpr MInt operator/(MInt lhs, MInt rhs) { MInt res = lhs; res /= rhs; return res; } friend constexpr std::istream &operator>>(std::istream &is, MInt &a) { i64 v; is >> v; a = MInt(v); return is; } friend constexpr std::ostream &operator<<(std::ostream &os, const MInt &a) { return os << a.val(); } friend constexpr bool operator==(MInt lhs, MInt rhs) { return lhs.val() == rhs.val(); } friend constexpr bool operator!=(MInt lhs, MInt rhs) { return lhs.val() != rhs.val(); } }; template<> int MInt<0>::Mod = 1; template constexpr MInt

CInv = MInt

(V).inv(); constexpr int P = 998244353; using Z = MInt

; int main() { std::ios::sync_with_stdio(false); std::cin.tie(nullptr); int N, M; std::cin >> N >> M; std::vector A(N); for (int i = 0; i < N; i++) { std::cin >> A[i]; } int lcm = 1; for (int i = 0; i < N; i++) { lcm = std::lcm(lcm, A[i]); } Z ans = 0; std::vector> p; int x = lcm; for (int i = 2; i * i <= x; i++) { if (x % i == 0) { int t = 0; while (x % i == 0) { x /= i; t += 1; } p.emplace_back(i, t); } } if (x > 1) { p.emplace_back(x, 1); } std::function dfs = [&](int i, int x, int phi) { if (i == p.size()) { int d = lcm / x; i64 sum = 0; for (int i = 0; i < N; i++) { sum += std::gcd(A[i], d); } ans += phi * power(Z(M), sum); return; } for (int j = 0; j <= p[i].second; j++) { if (j == 1) { phi *= p[i].first - 1; x *= p[i].first; } else if (j > 1) { phi *= p[i].first; x *= p[i].first; } dfs(i + 1, x, phi); } }; dfs(0, 1, 1); ans /= lcm; std::cout << ans << "\n"; return 0; }