UniqueSubsequence←{
⍝ Recursive to find unique subsequences
⍝ matching ⍵ located in ⍺
⍝ For each of ⊃⍵ in ⍺:
 ⍝ For each next appearing after it
  ⍝ And so on...
     0=≢⍵:1
     +/∊((⍸⍺∊⊃⍵)↓¨⊂⍺)∇¨⊂1↓⍵

 }