#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx")
#pragma GCC optimize("unroll-loops")
//#pragma warning(disable : 4996)

#ifdef _MSC_VER
#include <intrin.h>
#define __builtin_popcount __popcnt
#define __builtin_popcountll __popcnt64
#endif

#include <limits.h>
#include <math.h>
#include <time.h>

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <complex>
#include <cstdio>
#include <cstring>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;

#define REP(i, n) for (int i = 0; i < (n); ++i)
#define REPR(i, n) for (int i = n - 1; i >= 0; --i)
#define FOR(i, m, n) for (int i = m; i < n; ++i)
#define FORR(i, m, n) for (int i = m - 1; i >= n; --i)
#define SORT(v, n) sort(v, v + n);
#define VSORT(v) sort(v.begin(), v.end());
#define REVERSE(v, n) reverse(v, v + n);
#define VREVERSE(v) reverse(v.begin(), v.end())
#define ll long long
#define print(x) cout << (x) << '\n'
#define pe(x) cout << (x) << " "
#define DEBUG(x) cout << #x << ": " << x << endl
#define lb(v, n) lower_bound(v.begin(), v.end(), (n))
#define ub(v, n) upper_bound(v.begin(), v.end(), (n))
#define int long long
//#define double long double
#define all(x) (x).begin(), (x).end()
#define print_space(v) REP(i, v.size()) cout << v[i] << " \n"[i==(int)v.size()-1]
template <typename T1, typename T2> inline void chmin(T1& a, T2 b) { if (a > b) a = b; }
template <typename T1, typename T2> inline void chmax(T1& a, T2 b) { if (a < b) a = b; }
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
std::random_device rd;
std::mt19937 mt(rd());
constexpr ll MOD = 1e9 + 7;
constexpr int MAX = 500050;
const double pi = acos(-1);
constexpr double EPS = 1e-8;
constexpr ll LINF = 1e18 + 1;
constexpr int INF = 1e9 + 1;
//int dx[4] = { 0,0,-1,1 }, dy[4] = { 1,-1,0,0 };


template< typename flow_t >
struct Dinic {
	const flow_t INF;

	struct edge {
		int to;
		flow_t cap;
		int rev;
		bool isrev;
		int idx;
	};

	vector< vector< edge > > graph;
	vector< int > min_cost, iter;

	Dinic(int V) : INF(numeric_limits< flow_t >::max()), graph(V) {}

	void add_edge(int from, int to, flow_t cap, int idx = -1) {
		graph[from].push_back({ to, cap, (int)graph[to].size(), false, idx });
		graph[to].push_back({ from, 0, (int)graph[from].size() - 1, true, idx });
	}

	bool bfs(int s, int t) {
		min_cost.assign(graph.size(), -1);
		queue< int > que;
		min_cost[s] = 0;
		que.push(s);
		while (!que.empty() && min_cost[t] == -1) {
			int p = que.front();
			que.pop();
			for (auto &e : graph[p]) {
				if (e.cap > 0 && min_cost[e.to] == -1) {
					min_cost[e.to] = min_cost[p] + 1;
					que.push(e.to);
				}
			}
		}
		return min_cost[t] != -1;
	}

	flow_t dfs(int idx, const int t, flow_t flow) {
		if (idx == t) return flow;
		for (int &i = iter[idx]; i < graph[idx].size(); i++) {
			edge &e = graph[idx][i];
			if (e.cap > 0 && min_cost[idx] < min_cost[e.to]) {
				flow_t d = dfs(e.to, t, min(flow, e.cap));
				if (d > 0) {
					e.cap -= d;
					graph[e.to][e.rev].cap += d;
					return d;
				}
			}
		}
		return 0;
	}

	flow_t max_flow(int s, int t) {
		flow_t flow = 0;
		while (bfs(s, t)) {
			iter.assign(graph.size(), 0);
			flow_t f = 0;
			while ((f = dfs(s, t, INF)) > 0) flow += f;
		}
		return flow;
	}

	void output() {
		for (int i = 0; i < graph.size(); i++) {
			for (auto &e : graph[i]) {
				if (e.isrev) continue;
				auto &rev_e = graph[e.to][e.rev];
				cout << i << "->" << e.to << " (flow: " << rev_e.cap << "/" << e.cap + rev_e.cap << ")" << endl;
			}
		}
	}
};

//Ford-Fulkerson法で最大流を求める O(F|E|)
const int MAX_V = 500;
struct edge { int to, cap, rev; };
vector<edge>G[MAX_V];
bool used[MAX_V];

void add_edge(int from, int to, int cap) {
	G[from].push_back({ to, cap, G[to].size() });
	G[to].push_back({ from,0,G[from].size() - 1 });
}
int dfs(int v, int t, int f) {
	if (v == t)return f;
	used[v] = true;
	for (int i = 0; i < G[v].size(); i++) {
		edge &e = G[v][i];
		if (!used[e.to] && e.cap > 0) {
			int d = dfs(e.to, t, min(f, e.cap));
			if (d > 0) {
				e.cap -= d;
				G[e.to][e.rev].cap += d;
				return d;
			}
		}
	}
	return 0;
}
int max_flow(int s, int t) {
	int flow = 0;
	for (;;) {
		memset(used, 0, sizeof(used));
		int f = dfs(s, t, INF);
		if (f == 0) {
			return flow;
		}
		flow += f;
	}
}

void solve() {
	int N; cin >> N;
	vector<int>A(N + 1);
	FOR(i, 1, N + 1)cin >> A[i];
	ll ans = 0;
	FOR(i, 1, N + 1) {
		if (A[i] > 0)ans += A[i];
	}
	//Dinic<int>G(N + 2);
	int s = 0, t = N + 1;
	FOR(i, 1, N + 1) {
		if (A[i] >= 0) {
			add_edge(s, i, 0);
			add_edge(i, t, A[i]);
		}
		else {
			add_edge(s, i, -A[i]);
			add_edge(i, t, 0);
		}
		for (int k = 2; i*k <= N; k++) {
			add_edge(i,i*k, LINF);
		}
	}
	ll pena = max_flow(s, t);
	print(ans - pena);
}



signed main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	//int q;
	//cin >> q;
	//while (q--)
	solve();

}


Measured memory_bytes: 3732