#!/usr/bin/env PyPy3

from collections import Counter, defaultdict, deque
import itertools
import re
import math
from functools import reduce
import operator
import bisect
from heapq import *
import functools
mod=998244353

import sys
input=sys.stdin.readline
def divisor(n):
    sq = n**0.5
    border = int(sq)
    table = []
    bigs = []
    for small in range(1, border+1):
        if n%small == 0:
            table.append(small)
            big = n//small
            bigs.append(big)
    if border == sq:#nが平方数
        bigs.pop()
    table += reversed(bigs)
    return table
n,m=map(int,input().split())
a=list(map(int,input().split()))
open = [0] * (n+1)
div = []
for i in range(1,n+1):
    div.append(divisor(i))
for i in range(1,n+1):
    for j in div[i-1]:
        open[j] ^= 1
fact = [0] * (n+1)
for aa in a:
    fact[aa] = 1
ans = 0


for i in range(1,n+1)[::-1]:
    #print(open,fact)
    if fact[i] != open[i]:
        ans += 1
        for j in div[i-1]:
            open[j] ^= 1
print(ans)