import sys
import math

def main():
    n = int(sys.stdin.readline())
    a = list(map(int, sys.stdin.readline().split()))
    min_a = min(a)
    total = 0
    for num in a:
        gcd = math.gcd(num, min_a)
        lcm = (num * min_a) // gcd
        total += lcm
    total -= min_a
    print(total)

if __name__ == "__main__":
    main()