<sequence values="RDAUBW" origin="Center">
  <prl in="*R" out="*U" symmetry="()"/>
  <prl in="U*" out="B*" symmetry="()"/>
  <all in="DB*" out="*AD"/>
  <prl in="A" out="D" p="0.517" steps="1"/>
  <prl in="A" out="B"/>
  <path from="R" to="U" on="D" color="W"/>
</sequence>