WOLFRAM|DEMONSTRATIONS PROJECT

One Disk Per Diagonal

Each diagonal parallel to the main diagonal (which is blank) is colored with one color. The objective is to have exactly one disk on each diagonal, which is equivalent to finding the adjacency matrix of a graceful graph.
Clicking the button in the
th
i
row and
th
j
column first swaps the shapes (but not the colors) in rows
i
and
j
, and then swaps the shapes (but not the colors) in columns
i,j
.