fl=open('input.pyx','r').read().split('\n')
N=int(fl[0])
A=list(map(int,fl[1].split(' ')))

sum=0
for i in range(N):
    print('Proseccing %d%%'%(int(i/N*100)))
    for j in range(i,N):
        if i==j:continue
        sum+=A[i]%A[j]
        sum+=A[j]%A[i]
print(sum)