require 'prime'

class Integer
  def divisor_list
    return [] if self <= 0
    return [1] if self == 1

    prime_division.map{|e| [*(0..e.last)].map{|v| e.first ** v }}.inject{|res, e| res.map{|t| e.map{|v| t * v}}.flatten}.sort
  end
end

class Yukicoder
  def initialize
    n, p0 = gets.chomp.split(' ').map(&:to_f)
    n = n.to_i

    rate = 0.0

    2.upto(n) do |num|
      if num.prime?
        rate += 1
      else
        rate += (1 - p0) ** (num.divisor_list.size - 2)
      end
    end

    puts rate
  end
end

Yukicoder.new