c:\@Work\Perl\monks>perl -wMstrict -le
"my @things = qw(
   zero one two  three four five  six seven eight  nine ten eleven
   twelve thirteen fourteen  fifteen sixteen seventeen
   );
 ;;
 use constant COLS => 3;
 use constant FMT  => '%10s ' x COLS;
 ;;
 for my $max (0 .. $#things) {
   my @stuff = @things[0 .. $max];
   my $k = @stuff / COLS;
   $k = int($k + 1) if int($k) != $k;
   ;;
   my @rows;
   $rows[$_ % $k][$_ / $k] = $stuff[$_] for 0 .. $#stuff;
   ;;
   for my $ar_row (@rows) {
     printf qq{${ \FMT }\n}, @$ar_row, ('') x COLS;
     }
   print '--------------';
   }
"

##</code><code>##

      zero
--------------
      zero        one
--------------
      zero        one        two
--------------
      zero        two
       one      three
--------------
      zero        two       four
       one      three
--------------
      zero        two       four
       one      three       five
--------------
      zero      three        six
       one       four
       two       five
--------------
...
...
--------------
      zero        six     twelve
       one      seven   thirteen
       two      eight   fourteen
     three       nine    fifteen
      four        ten
      five     eleven
--------------
      zero        six     twelve
       one      seven   thirteen
       two      eight   fourteen
     three       nine    fifteen
      four        ten    sixteen
      five     eleven
--------------
      zero        six     twelve
       one      seven   thirteen
       two      eight   fourteen
     three       nine    fifteen
      four        ten    sixteen
      five     eleven  seventeen
--------------