#pragma GCC target("avx") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; typedef long long ll; typedef vector vl; typedef vector vvl; typedef vector vc; typedef vector vs; typedef vector vb; typedef vector vd; typedef pair P; typedef pair pii; typedef vector

vpl; typedef tuple tapu; #define rep(i,n) for(int i=0; i<(n); i++) #define REP(i,a,b) for(int i=(a); i<(b); i++) #define all(x) (x).begin(), (x).end() #define rall(x) (x).rbegin(), (x).rend() const int inf = 1<<30; const ll linf = 1LL<<62; const int MAX = 1020000; ll dy[8] = {1,-1,0,0,1,-1,1,-1}; ll dx[8] = {0,0,1,-1,1,-1,-1,1}; const double pi = acos(-1); const double eps = 1e-10; template inline bool chmin(T1 &a,T2 b){ if(a>b){ a = b; return true; } else return false; } template inline bool chmax(T1 &a,T2 b){ if(a inline void print(T &a){ for(auto itr = a.begin(); itr != a.end(); itr++){ cout << *itr << " "; } cout << "\n"; } template inline void print2(T1 a, T2 b){ cout << "debug: " << a << " " << b << "\n"; } template inline void print3(T1 a, T2 b, T3 c){ cout << "debug: " << a << " " << b << " " << c << "\n"; } void mark() {cout << "#" << "\n";} ll pcount(ll x) {return __builtin_popcountll(x);} const int mod = 1e9 + 7; //const int mod = 998244353; ll GCD(ll a, ll b){ if(b==0) return a; else return GCD(b,a%b); } int main(){ int n,m; cin >> n >> m; vl a(m); rep(i,m) cin >> a[i]; ll ans = 0; vl cnt(n+1,0); vl add(n+1,0); for(int i=1; i<=n; i++){ add[i] += i; cnt[i] += add[i]; for(int j=i+i; j<=n; j+=i){ cnt[j] += add[i] * (j / i); add[j] -= add[i]; } } rep(i,m){ ans += cnt[a[i]] - a[i]; } cout << ans << "\n"; }