def make_divisors(n):
    lower_divisors , upper_divisors = [], []
    i = 1
    while i*i <= n:
        if n % i == 0:
            lower_divisors.append(i)
            if i != n // i:
                upper_divisors.append(n//i)
        i += 1
    return lower_divisors + upper_divisors[::-1]

N,M = map(int, input().split())
A = list(map(int, input().split()))
if not (1<=N<=2*10**5 and 0<=M<=N and len(A)==M and A==sorted(A) and M == len(set(A))):
    exit()
for a in A:
    if 1<=a<=N:
        continue
    exit()

DIV = [[]]
ALL = [0]*(N+1)
DOOR= [0]*(N+1)
for i in range(1,N+1):
    DIV.append(make_divisors(i))
    for div in DIV[i]:
        ALL[div] = (ALL[div]+1)%2
for a in A:
    DOOR[a]=1

cnt = 0
for i in reversed(range(N+1)):
    if ALL[i]!=DOOR[i]:
        cnt+=1
        for div in DIV[i]:
            DOOR[div] = (DOOR[div]+1)%2
print(cnt)