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: 5, 20, ['B', '8773', '7997', '4583', '467', '4563', 'k', 'R', 'l', 'i', 'f', '5331', '2605', '3969', 'E', '9229', 'c', 'O', 'a', 'm', '1321', 'p']

maOc9229E396926055331filRk4563467