[ times
      [ [] swap behead
        swap witheach
          [ tuck dip [ - join ] ]
        drop ] ]                  is f-diff ( [ n --> [ )

  ' [ 90 47 58 29 22 32 55 5 55 73 ]

  dup size times
    [ dup i^
      dup echo say ": "
      f-diff echo cr ]
  drop