http://www.perlmonks.org?node_id=81761


in reply to (Golf): Sieve of Eratosthenes

Ok, how's 50 characters for the bonus: 
sub sieve {
  grep!(map$_[$a*$_]++,1..$_[0]/($a=$_))[0],2..$_[0]
}

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update: Hmm, in my golfing frenzy, I seem to have increased the big-O back to that of the main problem, so I don't think this qualifies after all. 
   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

In Section Meditations