#include<iostream>
#include<cstdio>
#include<algorithm>
using std::cin;using std::cout;
constexpr int N=1000006,V=522;
int n,k;
long long a[N],f[N];
namespace sub1_9{
	signed main(){
		for(int i=2;i<=n;++i)
			for(int j=1;j<i;++j)
				f[i]=std::max(f[i],f[j]+(a[j]&a[i]));
		cout<<*std::max_element(f+1,f+n+1);
		return 0;
	}
}
namespace sub10_13{
	long long b[V];
	signed main(){
		for(int i=0;i<512;++i) b[i]=-1e18;
		b[a[1]]=0;
		for(int i=2;i<=n;++i){
			for(int j=0;j<512;++j) f[i]=std::max(f[i],b[j]+(j&a[i]));
			if(f[i]>b[a[i]]) b[a[i]]=f[i];
		}
		cout<<*std::max_element(f+1,f+n+1);
		return 0;
	}
}
signed main(){
//	freopen("rose.in","r",stdin);
//	freopen("rose.out","w",stdout);
	std::ios::sync_with_stdio(false);
	cin.tie(nullptr);cout.tie(nullptr);
	cin>>n;for(int i=1;i<=n;++i) cin>>a[i];k=*std::max_element(a+1,a+n+1);
	if(n<=5000) return sub1_9::main();
	if(k<512) return sub10_13::main();
	return sub10_13::main();cout<<"芙羽心音";
}//第一百三回 施毒计金桂自焚身 昧真禅雨村空遇旧