(defn aswap! [array i j]
  (let [ai (aget array i)
        aj (aget array j)]
    (aset array i aj)
    (aset array j ai)))

(defn drive-to! [array n]
  (doseq [i (range 0 n)]
    (aswap! array i (inc i))))

(defn move-elements-to-the-end [array n]
  (loop [i 1, dest (dec (alength array))]
    (when (<= i n) (do (drive-to! array dest)
                       (recur (inc i) dest))))
  array)

дебаг
(1 2 3 4 5 6 7)
(2 1 3 4 5 6 7)
(2 3 1 4 5 6 7)
(2 3 4 1 5 6 7)
(2 3 4 5 1 6 7)
(2 3 4 5 6 1 7)
(2 3 4 5 6 7 1)
(3 2 4 5 6 7 1)
(3 4 2 5 6 7 1)
(3 4 5 2 6 7 1)
(3 4 5 6 2 7 1)
(3 4 5 6 7 2 1)
(3 4 5 6 7 1 2)
(4 3 5 6 7 1 2)
(4 5 3 6 7 1 2)
(4 5 6 3 7 1 2)
(4 5 6 7 3 1 2)
(4 5 6 7 1 3 2)