(define (test a) (extend '() (sequence 1 a)))(test 4);-> (1 2 3 4)(test 4);-> (1 2 3 4 1 2 3 4)(test 4);-> (1 2 3 4 1 2 3 4 1 2 3 4)test;-> (lambda (a) (extend '(1 2 3 4 1 2 3 4) (sequence 1 a)))