Contents

# coding: utf-8
class Integer
  # An emrip is a prime whose reversed digits give a different prime. For
  # example, 17 is an emrip because 71 is also prime.
  #
  # Returns true if self is an emrip; false otherwise.
  #
  #     1009.emrip?  #=> true
  #     1193.emrip?  #=> true
  #     7.emrip?     #=> false
  #
  def emrip?
    prime? and reverse != self and reverse.prime?
  end
end

Version data entries

4 entries across 4 versions & 1 rubygems

Version	Path
numb-0.152.0	lib/numb/emrip.rb
numb-0.138.0	lib/numb/emrip.rb
numb-0.125.0	lib/numb/emrip.rb
numb-0.114.0	lib/numb/emrip.rb