YES

(format LCTRS :logic QF_LIA)
(fun f2 1 :sort (Int Int))
(fun u_27 2 :sort (Int Int Int))

(rule (u_27 n_0 w_6_1) (+ (+ n_0 (- n_0 1)) w_6_1) :vars ((n_0 Int) (w_6_1 Int)))
(rule (f2 n_2) (u_27 n_2 (f2 (- n_2 2))) :guard (> n_2 1) :vars ((n_2 Int)))
(rule (f2 n_3) n_3 :guard (<= n_3 1) :vars ((n_3 Int)))

Confluent by Parallel Closedness with proof:
no critical pairs

Elapsed Time:  13.15 ms