(:trajectory

(:state (clear b1) (clear b2) (clear b3) (handempty) (ontable b1) (ontable b2) (ontable b3))

(:action (pick_up b2))

(:state (clear b1) (clear b3) (holding b2) (ontable b1) (ontable b3))

(:action (stack b2 b1))

(:state (clear b2) (clear b3) (handempty) (on b2 b1) (ontable b1) (ontable b3))

(:action (pick_up b3))

(:state (clear b2) (holding b3) (on b2 b1) (ontable b1))

(:action (stack b3 b2))

(:state (clear b3) (handempty) (on b2 b1) (on b3 b2) (ontable b1))

)