"George Ogata" <george.ogata / gmail.com> writes:

>> class Fixnum
>>   def divisors
>>     @d ||= (2..self/2).select{|i| self % i == 0 }
>
>      You've probably already realized this, but this would be a lot faster:
>
>      @d ||= (2..Math.sqrt(self)).select{|i| self % i == 0 }
>
>>   end
>> end

You reminded me of
      http://butunclebob.com/ArticleS.UncleBob.PerformanceTuning
-- 
Christian Neukirchen  <chneukirchen / gmail.com>  http://chneukirchen.org