#include<bits/stdc++.h> using namespace std; #pragma GCC optimize("O3") #define rep(i,n) for(ll i=0;i<n;i++) #define repl(i,l,r) for(ll i=(l);i<(r);i++) #define per(i,n) for(ll i=(n)-1;i>=0;i--) #define perl(i,r,l) for(ll i=r-1;i>=l;i--) #define fi first #define se second #define ins insert #define pqueue(x) priority_queue<x,vector<x>,greater<x>> #define all(x) (x).begin(),(x).end() #define CST(x) cout<<fixed<<setprecision(x) #define rev(x) reverse(x); using ll=long long; using vl=vector<ll>; using vvl=vector<vector<ll>>; using pl=pair<ll,ll>; using vpl=vector<pl>; using vvpl=vector<vpl>; const ll MOD=1000000007; const ll MOD9=998244353; const int inf=1e9+10; const ll INF=4e18; const ll dy[9]={1,0,-1,0,1,1,-1,-1,0}; const ll dx[9]={0,1,0,-1,1,-1,1,-1,0}; template <typename T> inline bool chmax(T &a, T b) { return ((a < b) ? (a = b, true) : (false)); } template <typename T> inline bool chmin(T &a, T b) { return ((a > b) ? (a = b, true) : (false)); } int main(){ ll n;cin >> n; vl v(n);rep(i,n)cin >> v[i]; vl rv=v;rev(all(rv)); vpl pls(n);rep(i,n)pls[i]={v[i],i};sort(all(pls)); vpl rpls(n);rep(i,n)rpls[i]={rv[i],i};sort(all(rpls)); ll ans=0; for(ll k=1;k<=n;k++){ vl left(n/k); vl deg(n/k); rep(j,n){ if(pls[j].second>=n/k*k)continue; deg[pls[j].second/k]++; if(deg[pls[j].second/k]==(k+1)/2)left[pls[j].second/k]=pls[j].first*k; } rep(i,n/k-1)left[i+1]+=left[i]; vl lcum(n/k+1);rep(i,n/k)lcum[i+1]=max(lcum[i],left[i]); vl right(n/k); vl rdeg(n/k); rep(j,n){ if(rpls[j].second>=n/k*k)continue; rdeg[rpls[j].second/k]++; if(rdeg[rpls[j].second/k]==(k+1)/2)right[rpls[j].second/k]=rpls[j].first*k; } rep(i,n/k-1)right[i+1]+=right[i]; vl rcum(n/k+1);rep(i,n/k)rcum[i+1]=max(rcum[i],right[i]); //rep(i,n/k+1)cout << lcum[i] <<" ";cout << endl; //rep(i,n/k+1)cout << rcum[i] <<" ";cout << endl; rep(i,n/k+1)chmax(ans,lcum[i]+rcum[n/k-i]); } cout << ans << endl; }