This has been an interesting thread to follow. I played around with a Bit Vector algorithm... going for efficiency at the cost of a little brevity. Here's what I came up with:

#!usr/bin/perl -w
use Benchmark;

timethese(100,{
 Adam => sub { 
    @_=(1);
  L:for(2..1000) {
      $i=-@_;        #updated per node 20757 7/13/2000
      while(++$i){   #ditto
          next L if!($_%$_[$i])
      }
      push@_,$_
    }
    #print join "\t", @_;
  },

 Maverick => sub { 
    for(1..1000){
      push@_,$_;
      for(@_[1..$#_-1]){
        pop@_&&last if!($_[-1] %$_)
      }
    }
    #print join "\t", @_;
  },

 Ase => sub {
    $v='1' x 1000;
    for(2..1000){
      next if !vec($v,$_-1,8);
      for($q=$_*2;$q<1001;$q+=$_){
         vec($v,$q-1,8)=0
      }
    }
   #print join "\t",grep {vec($v,$_-1,8)} (1..1000);
  },

});
[download]

Here's a table summarizing the data:

Routine	N	Iterations	Time
Adam	1000	100	5
Ase	1000	100	2
Maverick	1000	100	2
Adam	10000	100	203
Ase	10000	100	21
Maverick	10000	100	24
Ase	100000	100	221
Maverick	100000	100	236

Benchmark is your friend!

It seems Mavericks code is only very slightly slower with the benefit of being slightly shorter.

This was done on a 300 mHz amd K6 running win 98 and perl 5.005_02 (activestate 509) as always your mileage may vary.

Update 7/13/2000: I modified Adam's code per this node and re-benchmarked accordingly.
-ase

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