TABLE(0, 0):
head0,head1,head2,head3
 0/0  colspan=4  ,,,
 1/0  rowspan=2  , 1/1 , 1/2  , 1/3  
, 2/1 colspan=2 rowspan=3  ,, 2/3 
 3/0  ,,, 3/3 
 4/0  ,,, 4/3 
 5/0 colspan=2  ,, 5/2 , 5/3 
(
  ["head0", "head1", "head2", "head3"],
  [" 0/0  colspan=4  ", undef, undef, undef],
  [" 1/0  rowspan=2  ", " 1/1 ", " 1/2  ", " 1/3  "],
  [undef, " 2/1 colspan=2 rowspan=3  ", undef, " 2/3 "],
  [" 3/0  ", undef, undef, " 3/3 "],
  [" 4/0  ", undef, undef, " 4/3 "],
  [" 5/0 colspan=2  ", undef, " 5/2 ", " 5/3 "],
)