#include<bits/stdc++.h>
using namespace std;
using ll = long long;
using VI = vector<ll>;
using VV = vector<VI>;
using VS = vector<string>;

// tourist set
template <typename A, typename B>
string to_string(pair<A, B> p);

template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);

template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);

string to_string(const string& s) {
  return '"' + s + '"';
}

string to_string(const char* s) {
  return to_string((string) s);
}

string to_string(bool b) {
  return (b ? "true" : "false");
}

string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}

template <size_t N>
string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}

template <typename A>
string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto &x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}

template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}

template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ")";
}

template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}

void debug_out() { cerr << '\n'; }

template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}

#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif
// tourist set end

template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }

#define FOR(i,a,b) for(ll i=(a);i<(b);++i)
#define rep(i,b) FOR(i, 0, b)
#define ALL(v) (v).begin(), (v).end()
#define p(s) cout<<(s)<<'\n'
#define p2(s, t) cout << (s) << " " << (t) << '\n'
#define br() p("")
#define pn(s) cout << (#s) << " " << (s) << '\n'
#define p_yes() p("YES")
#define p_no() p("NO")
#define SZ(x) ((int)(x).size())
#define SORT(A) sort(ALL(A))
#define RSORT(A) sort(ALL(A), greater<ll>())

void no(){p_no(); exit(0);}
void yes(){p_yes(); exit(0);}

const ll mod = 1e9 + 7;
const ll inf = 1e18;
const double PI = acos(-1);

// 最大流用の辺
struct Edge{
    ll to;
    ll capacity;
    ll rev; // index
    Edge(ll t, ll c, ll r){
        to = t;
        capacity = c;
        rev = r;
    }
    Edge(){}
};
 
// ford fulkerson ver
struct MaxFlow{
    vector<vector<Edge> > G;
    vector<bool> used;
 
    MaxFlow(ll node_num){
        G.resize(node_num);
        used.resize(node_num);
    }
 
    void add_edge(ll from, ll to, ll capacity){
        G[from].push_back(Edge(to, capacity, G[to].size()));
        G[to].push_back(Edge(from, 0, G[from].size()-1));
    }
 
    ll dfs(ll v, ll t, ll flow){
        if(v==t) return flow;
        used[v] = true;
        for(Edge &edge : G[v]){
            if(!used[edge.to] && edge.capacity > 0){
                ll d = dfs(edge.to, t, min(flow, edge.capacity));
                if(d>0){
                    edge.capacity -= d;
                    G[edge.to][edge.rev].capacity += d;
                    return d;
                }
            }
        }
        return 0;
    }
 
    ll calc(ll start, ll end){
        ll flow_sum = 0;
        while(true){
            fill(ALL(used), false);
            ll f = dfs(start, end, inf);
            if(f==0){
                break;
            }
            flow_sum += f;
        }
        return flow_sum;
    }
};

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);

    // input
    ll N; 
    cin >> N;

    VI A(N);
    rep(i, N){
        cin >> A.at(i);
    }

    MaxFlow flow(N+2);
    
    // 0 start
    // 1-N node
    // N+1 sink

    ll sum = 0;
    rep(i, N){
      ll id = i+1;
      ll a = A[i];

      if(a>=0){
        sum += a; // 無条件で貰えるお金
        flow.add_edge(0, id, a); // waru
        flow.add_edge(id, N+1, 0);
      }else{
        flow.add_edge(0, id, 0);
        flow.add_edge(id, N+1, -a);
      }
    }

    FOR(i, 1, N){
      // iの倍数へのエッジ
      FOR(m, 2, 101){
        if(i*m>N)break;

        // i to m*i
        // flow.add_edge(i, m*i, inf);
        flow.add_edge(m*i, i, inf);
      }
    }

    ll penalty = flow.calc(0, N+1);
    debug(penalty);
    ll ans = sum - penalty;
    p(ans);
    
    return 0;
}

Measured memory_bytes: 256