#nexus
[This file provided by Paul Lewis, from the NCL test suite. ]

begin taxa;
  dimensions ntax=8;
  taxlabels taxon_1 taxon_2 taxon_3 taxon_4 taxon_5 taxon_6 taxon_7 taxon_8;
end;

[!
************************************************
* Non-interleaved, lower-triangular, diagonals *
************************************************
]
begin distances;
  matrix
    taxon_1    0
    taxon_2    1   0
    taxon_3    2   3   0
    taxon_4    4   5   6   0
    taxon_5    7   8   9  10   0
    taxon_6   11  12  13  14  15   0
    taxon_7   16  17  18  19  20  21   0
    taxon_8   22  23  24  25  26  27  28   0;
end;
