A knight’s tour is a sequence of knight’s moves such that each square on the
board is visited exactly once. An Aztec diamond is a square board of size
where triangular
regions of side length
have been removed from all four corners.
We show that the existence of knight’s tours on Aztec diamonds cannot be proved
inductively via smaller Aztec diamonds, and explain why a divide-and-conquer
approach is also not promising. We then describe two algorithms that aim to
efficiently find knight’s tours on Aztec diamonds. The first is based on random walks,
a straightforward but limited technique that yielded tours on Aztec diamonds for all
apart
from
.
The second is a path-conversion algorithm that finds a solution for all
. We
then apply the path-conversion algorithm to random graphs to test the robustness of
our algorithm. Online supplements provide source code, output and more details
about these algorithms.