Towers of Hanoi planning domain.
This planning domain is a generalization of the well known
puzzle. The original game consists of three pegs and a number
of discs of different sizes stacked on pegs. It is possible
to move a disc on the top of one peg to another peg in each
turn. The condition that a smaller disc is always on larger
disc must be preserved throughout the game. Our generalization
is that we use arbitrary number of pegs and more than one
disc can be moved in each turn. We can pick for example
two discs and then place them in a different order than they
were picked. The original game starts with all disc stacked
on the first peg. However we allow arbitrary configuration
(satisfying the condition on disc sizes) as the starting point
in our generalization. Originally, the objective is to move
all discs to the last third peg. Again we allow arbitrary
valid configuration as a goal.