m = gets.to_i
n = gets.to_i
c_list = gets.chomp.split.map(&:to_i)

prime_list = [2]
3.upto(10000) do |i|
  prime_list.push(i) if prime_list.none? {|p| i % p == 0} 
end

dp = Array.new(10001, -1)
dp[m] = 0
c_list.each do |c|
  m.downto(1) do |j|
    k = j - c
    next if dp[j] == -1
    break if k < 0
    dp[k] = [dp[k], dp[j] + 1].max
  end
end

result = 0
prime_list.each do |p|
  result += dp[p] if dp[p] != -1
end

result += dp.max
puts result