nwARGOS example: crown: sequence file
$crown
1coc
2coc
3coc
4coc
5coc
6coc 0 0 1 1
-2
0SPCE
-3
Note that the sixth coc segment's second link is pointing
to the first link atom of the first coc segment, to make
the cyclic crown ether. Alternatively this could have been specified
by letting the first coc segment's first link point to the
sixth coc segment's second link atom. The other coc
segments are automatically link their first link atom to their previous
segment's second link atom.