import sys
def divisors(num):
    l=[]
    i=1
    while i < num:
        if num % i == 0:
            l.append(i)
        i = i + 1
    return l

def longestSequence(a):
    total = []
    for i in a:
        m=divisors(i)
        sum=0
        for k in range(0,len(m),2):
            sum+=m[k]
        total.append(sum+i)
    result=reduce(lambda x,y:x+y,total)
    return result



if __name__ == "__main__":
    n = int(raw_input().strip())
    a = map(long, raw_input().strip().split(' '))
    result = longestSequence(a)
    print result