N = int(input())
A=[]
for i in range(N):
    A.append(int(input()))
counter = 0
for i in range(0, N):
    j = A[i] - 2
    if j == 0 or j == 1:
        counter += 1
    else:
        while j > 1:
            if i % j == 0:
                break
            else:
                j -= 1
        else:
            counter += 1
print(counter)