N,M = map(int,input().split())

if M == 0:
    print(N)
    exit()

A = list(map(int,input().split()))
B = [False]*(N+1)

for i,v in enumerate(A):
    if v:
        B[v] = True

ans = [1]*(N+1)

if N%2 == 0:
    tmp = N//2
else:
    tmp = N//2+1

for i in range(tmp,N+1):
    if not B[i]:
        ans[i] = 0

#print(ans)

for i in range(tmp,0,-1):
    tmp2 = N//i
    cnt = 0

    for j in range(tmp2):
        if ans[i*(j+1)] == 1:
            cnt+=1

    if tmp2%2 == 0 and B[i]:
        ans[i] = 0

print(sum(ans))