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

#define F first
#define S second
#define pb push_back

const long long MOD = 1e9 + 7;
const long long MAXN = 1e6 + 1;
using namespace std;

typedef long long ll;

long long readInt() {
    bool minus1 = false;
    long long result = 0;
    char ch;
    ch = getchar();
    while (true) {
        if (ch == '-') break;
        if (ch >= '0' && ch <= '9') break;
        ch = getchar();
    }
    if (ch == '-') minus1 = true; else result = ch-'0';
    while (true) {
        ch = getchar();
        if (ch < '0' || ch > '9') break;
        result = result*10 + (ch - '0');
    }
    if (minus1)
        return -result;
    else
        return result;
}

int a[MAXN];

int n;

const int MX = 251;
const ll INF = ll(1e17);
 


struct MaxFlow //by yutaka1999, have to define INF and MX (the Max number of vertices)
{
	struct edge
	{
		ll to,cap,rev;
		edge(ll to=0,ll cap=0,ll rev=0):to(to),cap(cap),rev(rev){}
	};
	vector <edge> vec[MX];
	ll level[MX];
	ll iter[MX];
	
	void addedge(int s,int t,ll c) //adds an edge of cap c to the flow graph
	{
		int S=vec[s].size(),T=vec[t].size();
		vec[s].push_back(edge(t,c,T));
		vec[t].push_back(edge(s,0,S));
	}
	void bfs(int s)
	{
		memset(level,-1,sizeof(level));
		queue <int> que;
		level[s] = 0;
		que.push(s);
		while (!que.empty())
		{
			int v = que.front();que.pop();
			for(int i=0;i<vec[v].size();i++)
			{
				edge&e=vec[v][i];
				if (e.cap>0&&level[e.to]<0)
				{
					level[e.to]=level[v]+1;
					que.push(e.to);
				}
			}
		}
	}
	ll flow_dfs(int v,int t,ll f)
	{
		if (v==t) return f;
		for(ll &i=iter[v];i<vec[v].size();i++)
		{
			edge &e=vec[v][i];
			if (e.cap>0&&level[v]<level[e.to])
			{
				ll d=flow_dfs(e.to,t,min(f,ll(e.cap)));
				if (d>0)
				{
					e.cap-=d;
					vec[e.to][e.rev].cap+=d;
					return d;
				}
			}
		}
		return 0;
	}
	ll maxflow(int s,int t) //finds max flow using dinic from s to t
	{
		ll flow = 0;
		while(1)
		{
			bfs(s);
			if (level[t]<0) return flow;
			memset(iter,0,sizeof(iter));
			while (1)
			{
				ll f=flow_dfs(s,t,INF);
				if(f==0) break;
				flow += f;
			}
		}
	}
};
MaxFlow mf;

int main() {
    n = readInt();
    int S = 111;
    long long sum = 0;
    int T = 112;
    for (int i = 1; i <= n; i++) {
        a[i] = readInt();
		if (a[i] < 0) {
			mf.addedge(S, i, -a[i]);		
		} else {
			mf.addedge(i, T, a[i]);
			sum += a[i];
		}    
    }                                                                                                           
	for (int i = 1; i <= n; i++) {
		for (int j = 2 * i; j <= n; j += i) {
			mf.addedge(i, j, ll(1e11));
		}
	}	                                                           
    cout << sum - mf.maxflow(S, T);                                             
    return 0;             
}

Measured memory_bytes: 256