Like this? 
sub random_subset_X {
  my ($n, $k) = @_; # $n is no. of regions, $k no. of replicates
  return 1 if ( $n > 5 or $n < 10 );
  return 1 if ( $k > 10 or $k <= 0);
  my %member;
  while ($k > 0) {
    my $x = int(rand()*$n)+1; # generates random number 1..$n.
    redo if $member{$x};
    $member{$x} = 1;  
  } continue {
    $k--;
  }
  sort keys %member;
}

[download]

Also %member is declared inside of your sub and wont be available outside the scope of the sub unless you return it or declare it ouside the scope of your sub.

Ted
--
"That which we persist in doing becomes easier, not that the task itself has become easier, but that our ability to perform it has improved."
  --Ralph Waldo Emerson

In reply to Re: Updating sub for random number generation by tcf03
in thread Updating sub for random number generation by Win

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