#ifdef LOCAL111
	#define _GLIBCXX_DEBUG
#else
	#define NDEBUG
#endif
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
const int INF = 1e9;
using namespace std;
template<typename T, typename U> ostream& operator<< (ostream& os, const pair<T,U>& p) { cout << '(' << p.first << ' ' << p.second << ')'; return os; }

#define endl '\n'
#define ALL(a)  (a).begin(),(a).end()
#define SZ(a) int((a).size())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define REP(i,n)  FOR(i,0,n)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)
#ifdef LOCAL111
	#define DEBUG(x) cout<<#x<<": "<<(x)<<endl
	template<typename T> void dpite(T a, T b){ for(T ite = a; ite != b; ite++) cout << (ite == a ? "" : " ") << *ite; cout << endl;}
#else
	#define DEBUG(x) true
	template<typename T> void dpite(T a, T b){ return; }
#endif
#define F first
#define S second
#define SNP string::npos
#define WRC(hoge) cout << "Case #" << (hoge)+1 << ": "
template<typename T> void pite(T a, T b){ for(T ite = a; ite != b; ite++) cout << (ite == a ? "" : " ") << *ite; cout << endl;}
template<typename T> bool chmax(T& a, T b){if(a < b){a = b; return true;} return false;}
template<typename T> bool chmin(T& a, T b){if(a > b){a = b; return true;} return false;}

typedef long long int LL;
typedef unsigned long long ULL;
typedef pair<int,int> P;

void ios_init(){
	//cout.setf(ios::fixed);
	//cout.precision(12);
#ifdef LOCAL111
	return;
#endif
	ios::sync_with_stdio(false); cin.tie(0);	
}

typedef long long cost_t;

class Edge {
public:
	int to = -1, from = -1, rev = -1;
	cost_t cost = -1, cap = -1;
	
	Edge(){
	}

	Edge(int x,cost_t y){
		to = x;
		cost = y;
	}

	Edge(int x, int y, cost_t z){
		from = x;
		to = y;
		cost = z;
	}

	Edge(int x, int y, int r, cost_t z){
		from = x;
		to = y;
		cost = z;
		rev = r;
	}

	Edge(int x, int y, int r, cost_t co, cost_t ca){
		from = x;
		to = y;
		cost = co;
		cap = ca;
		rev = r;
	}

	bool operator< (const Edge& x) const {
		if(cost != x.cost) return cost < x.cost;
		return to < x.to;
	}

	bool operator> (const Edge& x) const {
		if(cost != x.cost) return cost > x.cost;
		return to > x.to;
	}
};

class Graph {
private:
	typedef vector<Edge> Edges;
	//const long long int INF = (long long)1e18;
	vector<Edges> v; 
	int n;
public:
	Graph(int x){
		n = x;
		v = vector<Edges>(x);
	}

	Graph(){}

	Edges& operator[](int x){
		return v[x];
	}

	const Edges& operator[](int x) const {
		return v[x];
	}

	int size() const {
		return n;
	}

	void add_edge(int from, const Edge &e){
		v[from].push_back(e);
	}

	void add_edge(int from, int to, cost_t cost = -1, cost_t cap = -1, int rev = -1){
		add_edge(from,Edge(from,to,rev,cost,cap));
	}

	void add_fedge(int from, int to, cost_t cap = -1){
		add_edge(from,to,-1,cap,-1);
	}

	void add_uedge(int from, int to, cost_t cost = -1){
		add_edge(from,to,cost);
		add_edge(to,from,cost);
	}
};


vector<cost_t> bellmanford(const Graph& g, int from)
{
	vector<cost_t> res(g.size(),INF);
	res[from] = 0;
	bool conf = true;
	int cnt = 0;
	while(conf){
		conf = false;
		for(int i = 0; i < g.size(); i++){
			if(res[i] != INF)
			for(const auto& e : g[i]){
				if(res[e.to] > res[i]+e.cost){
					conf = true;
					res[e.to] = res[i]+e.cost;
				}
			}
		}
		if(cnt > g.size()+5) return vector<cost_t>();
		cnt++;
	}
	return res;
}

cost_t dMaxFlow(const Graph &g_, int s, int t){
	Graph g = g_;
	assert(s != t);
	int n = g.size();
	for(int i = 0; i < n; ++i) {
		for(int j = 0; j < int(g_[i].size()); j++) {
			auto&& e = g[i][j];
			e.rev = g[e.to].size();
			g.add_edge(e.to,i,-1,0,j);
		}
	}

	cost_t flow = 0;
	while(true){
		vector<int> level(n,-1);
		level[s] = 0;
		queue<int> que;
		que.push(s);
		while(!que.empty()) {
			int v = que.front();
			que.pop();
			for(auto&& e : g[v]) {
				if(e.cap > 0 and level[e.to] < 0){
					level[e.to] = level[v]+1;
					que.push(e.to);
				}
			}
		}

		if(level[t] < 0) return flow;

		vector<int> iter(n,0);
		function<cost_t(int, int)> dfs = 
		[&](int v, cost_t f) -> cost_t {
			if(v == t) return f;
			for(int& i = iter[v]; i < (int)g[v].size(); ++i) {
				auto& e = g[v][i];
				if(e.cap <= 0 or level[v] >= level[e.to]) continue;
				int d = dfs(e.to, min(f,e.cap));
				if(d > 0){
					e.cap -= d;
					g[e.to][e.rev].cap += d;
					return d;
				}
			}
			return 0;
		};

		cost_t f;
		while((f = dfs(s, INF)) > 0) {
			flow += f;
		}
	}
}

class GraphVizualizer{
	int cnt;
public:
	GraphVizualizer(){
		cnt = 0;
	}

	void operator() (const Graph &g, bool with_dir = true, bool with_cap = false){
		ofstream ofs("./out.dot");
		if(!with_dir) ofs << "graph graph_name {" << endl;
		else ofs << "digraph graph_name {" << endl;
		for(int i = 0; i < (int)g.size(); ++i) {
			ofs << "    " << i << "[];" << endl;
		}
		for(int i = 0; i < (int)g.size(); i++){
			if (!g[i].size())
				continue;
			for(const auto &e : g[i]){
				if(!with_dir){
					if(e.to > i) ofs << "    " << i << " -- " << e.to ; 
				}else ofs << "    " << i << " -> " << e.to ; 
				
				if (with_cap) {
					ofs << " [ label = \"" << (e.cost  == INF ? "inf" : to_string(e.cost)) << "\"];"; 
				}
				if(with_dir or e.to > i)ofs << endl;
			}
		}
		ofs << "}" << endl;
		ofs.close();
		string cmd = "dot -T png out.dot > ";
		cmd = cmd+"sample"+to_string(cnt)+".png";
		system(cmd.c_str());	
		cnt++;
	}
};



int main()
{
	ios_init();
	int n;
	GraphVizualizer viz;
	while(cin >> n) {
		vector<int> a(n);
		REP(i,n) cin >> a[i];
		Graph g(n+2);
		int s = n;
		int t = n+1;
		REP(i,n){
			REP(j,n) {
				if((j+1)%(i+1) == 0 && i != j) {
					g.add_fedge(j, i, INF);
				}
			}
		}
		REP(i,n) {
			if(a[i] < 0) {
				g.add_fedge(i, t, -a[i]);
			} else {
				g.add_fedge(s, i, a[i]);
			}
		}
		LL sum = 0;
		REP(i,n) sum += max(a[i], 0);
		cout << sum-dMaxFlow(g, s, t) << endl;
	}
	return 0;
}


Measured memory_bytes: 384