from itertools import dropwhile,accumulate
n=int(input())
a=list(dropwhile(lambda x:x==0,list(map(int,input().split()))[::-1]))[::-1]
n=len(a)
if any(a[i]>i+1 for i in range(n)):
    print("No")
    exit()
b=list(accumulate(a[::-1]))
for i in range(n):
    if b[i]%(n-i)!=0:
        print("No")
        break
else:
    print("Yes")