class Impairs
	def initialize(n)
		@cardinal = n
	end

	def each
		i = 1
		@cardinal.times do
			yield i
			i = i +2
		end
	end
end

class Integer
	def premiers_impairs
		Impairs.new(self)
	end
end

3.premiers_impairs.each do | i |
	puts i.to_s
end