//#include <bits/stdc++.h>

#include <iostream>
#include <algorithm>

#include <bitset>
#include <vector>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <stack>
#include <queue>
#include <deque>
#include <cstring>
#include <string>
#include <utility>
#include <array>
#include <complex>
#include <valarray>

#include <cassert>
#include <cmath>
#include <functional>
#include <iomanip>
#include <chrono>
#include <random>
#include <numeric>


using namespace std;
#define int long long

typedef long long ll;
typedef unsigned long long ull;
//typedef unsigned __int128 HASH;
typedef pair<int,int> pii;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pullull;
typedef pair<ll,int> plli;
typedef pair<double, int> pdbi;
typedef pair<int,pii> pipii;
typedef pair<ll,pll> plpll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<vi> vvi;
typedef vector<vvi> vvvi;
typedef vector<pii> vpii;
typedef vector<vector<int>> mat;

#define rep(i,n) for (int i=0;i<(n);i++)
#define rep2(i,a,b) for (int i=(a);i<(b);i++)
#define rrep(i,n) for (int i=(n);i>0;i--)
#define rrep2(i,a,b) for (int i=(a);i>b;i--)
#define pb push_back
#define fi first
#define se second
#define all(a) (a).begin(),(a).end()
#define rall(a) (a).rbegin(),(a).rend()

const ll hmod1 = 999999937;
const ll hmod2 = 1000000000 + 9;
const int INF = 1<<30;
const double EPS = 1e-12;
const ll mod = 1000000000 + 7;
const int dx4[4] = {1, 0, -1, 0};
const int dy4[4] = {0, 1, 0, -1};
const int dx8[8] = {1, 1, 1, 0, 0, -1, -1, -1};
const int dy8[8] = {0, 1, -1, 1, -1, 0, 1, -1};
const double pi = 3.141592653589793;

#define addm(X, Y) (X) = ((X) + ((Y) % mod) + mod) % mod
#define inside(y, x, h, w) (0 <= (y) && (y) < (h) && 0 <= (x) && (x) < (w)) ? true : false


const int MAX_V = 105;
struct edge {
    int to, cap, rev;
    edge(int to, int cap, int rev) :to(to), cap(cap), rev(rev) {}
};

vector<vector<edge>> g(MAX_V);
int level[MAX_V];
int iter[MAX_V];

void add_edge(int from, int to, int cap) {
    g[from].emplace_back(to, cap, g[to].size());
    g[to].emplace_back(from, 0, g[from].size() - 1);
}

void bfs(int s) {
    memset(level, -1, sizeof(level));
    queue<int> q;
    level[s] = 0;
    q.push(s);
    while (!q.empty()) {
        int now = q.front(); q.pop();
        for (auto e : g[now]) {
            if (e.cap > 0 && level[e.to] < 0) {
                level[e.to] = level[now] + 1;
                q.push(e.to);
            }
        }
    }
}

int dfs(int now, int t, int f) {
    if (now == t) return f;
    for (int &i = iter[now]; i < g[now].size(); i++) {
        edge &e = g[now][i];
        if (e.cap > 0 && level[now] < level[e.to]) {
            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;
    while (true) {
        bfs(s);
        if (level[t] < 0) return flow;
        memset(iter, 0, sizeof(iter));
        int f;
        while ((f = dfs(s, t, INF)) > 0) flow += f;
    }
}

int n;
int a[105];

signed main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    cin >> n;
    rep(i, n) cin  >> a[i];
    int s = n;
    int t = n + 1;
    int ans = 0;
    rep(i, n) {
        if (a[i] > 0) {
            add_edge(i, t, a[i]);
            ans += a[i];
        }
        else {
            add_edge(s, i, -a[i]);
        }
    }
    rep2(i, 1, n + 1) {
        rep2(j, i + 1, n + 1) {
            if (j % i == 0) {
                add_edge(i - 1, j - 1, INF);
            }
        }
    }
    cout << ans - max_flow(s, t) << endl;

}

Measured memory_bytes: 256