import itertools as iter
import collections as coll
import heapq as hq
import bisect as bis
from decimal import Decimal as dec
from functools import cmp_to_key
import math
import sys
#import pypyjit
#pypyjit.set_param('max_unroll_recursion=-1')
sys.setrecursionlimit(10 ** 6)
inp = sys.stdin.readline
input = lambda : inp().rstrip()
getN = lambda : int(inp())
getNs = lambda : map(int, inp().split())
getList = lambda :list(map(int, inp().split()))
getStrs = lambda n : [input() for _ in [0] * n]
def yexit(): print("Yes"); exit(0)
def nexit(): print("No"); exit(0)
pi = 3.141592653589793
mod = 1000000007
MOD = 998244353
INF = 4611686018427387903
dx = [1, 0, -1, 0];	dy = [0, 1, 0, -1]
#di = coll.defaultdict(int)


"""
Main Code
"""

n = getN()
a = getList()

if(n >= 16):
	print(65535)
	exit(0)

def shift(x):
	return (x >> 1) | ((x & 1) << 15)

st = set([0])
for k in a:
	bst = set([k])
	b = k
	for _ in [0]*16:
		b = shift(b)
		bst.add(b)
	nst = set([])
	for x in st:
		for y in bst:
			nst.add(x | y)
	st = set(nst)

print(max(st))