(:trajectory

(:state (clear b4) (handempty) (on b2 b1) (on b3 b2) (on b4 b3) (ontable b1))

(:action (unstack b4 b3))

(:state (clear b3) (holding b4) (on b2 b1) (on b3 b2) (ontable b1))

(:action (put_down b4))

(:state (clear b3) (clear b4) (handempty) (on b2 b1) (on b3 b2) (ontable b1) (ontable b4))

(:action (unstack b3 b2))

(:state (clear b2) (clear b4) (holding b3) (on b2 b1) (ontable b1) (ontable b4))

(:action (put_down b3))

(:state (clear b2) (clear b3) (clear b4) (handempty) (on b2 b1) (ontable b1) (ontable b3) (ontable b4))

(:action (pick_up b4))

(:state (clear b2) (clear b3) (holding b4) (on b2 b1) (ontable b1) (ontable b3))

(:action (stack b4 b2))

(:state (clear b3) (clear b4) (handempty) (on b2 b1) (on b4 b2) (ontable b1) (ontable b3))

)