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: 4, 20, ['5993', 's', '589', 'X', '383', '6337', 'k', '8525', 'j', 'R', 'b', 't', '6121', 'a', '3419', '8639', 'b', 'Y', 'J', 't', 'D', 'w']

tJYb86393419a6121tbRj8525k6337383X