Definition: In this task, you are given inputs i, j, and A, where i and j are integers and A is a list. You need to find all elements of A from the ith element to the jth element, reverse the order in which they occur, and then concatenate them to output the resultant string. i and j will be non-negative, and will always have a value less than the length of A. i will always be less than j. Perform the operations in order, i.e., do not concatenate the elements and then reverse the string.
Input: 6, 17, ['3387', '4857', 'X', 'R', '4385', 'U', '2849', '4767', '8623', '6641', '769', '2885', 'Z', '8019', '4547', '3007', '6239']

6239300745478019Z28857696641862347672849U