digraph RKMachine_4 {
  s0Up -> s1Up [label="a/0"]
  s0Up -> s0Dn [label="b/0"]
  s1Up -> s2Up [label="a/1"]
  s1Up -> s1Dn [label="b/0"]
  s2Up -> s3Up [label="a/2"]
  s2Up -> s2Dn [label="b/0"]
  s3Up -> s0Up [label="a/3"]
  s3Up -> s3Dn [label="b/0"]
  s0Dn -> s3Dn [label="a/0"]
  s0Dn -> s0Up [label="b/0"]
  s1Dn -> s0Dn [label="a/1"]
  s1Dn -> s1Up [label="b/0"]
  s2Dn -> s1Dn [label="a/2"]
  s2Dn -> s2Up [label="b/0"]
  s3Dn -> s2Dn [label="a/3"]
  s3Dn -> s3Up [label="b/0"]
}