// Think twice, code once.
#include <cstdio>
#include <string>
#include <cstring>
#include <iostream>
#include <algorithm>
#define eputchar(c) putc(c, stderr)
#define eprintf(...) fprintf(stderr, __VA_ARGS__)
#define eputs(str) fputs(str, stderr), putc('\n', stderr)
using namespace std;

int n, id[40];
long long a[1000005], dp[1000005], ans;

int main() {
	scanf("%d", &n);
	for (int i = 1; i <= n; i++) scanf("%lld", &a[i]);
	for (int i = 1; i <= n; i++) {
		dp[i] = dp[i - 1];
		for (int j = 0; j < 40; j++)
			if (a[i] >> j & 1) dp[i] = max(dp[i], dp[id[j]] + (a[id[j]] & a[i]));
		for (int j = 0; j < 40; j++)
			if (a[i] >> j & 1) id[j] = i;
		ans = max(ans, dp[i]);
	}
	printf("%lld\n", ans);
	return 0;
}