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: 3, 20, ['s', '3141', '873', 'N', '463', '8693', '3035', '6709', '531', '47', '5839', '2015', 'm', '2221', '1379', 'a', '4067', '5103', '5243', 'R', '8517']

R524351034067a13792221m2015583947531670930358693463N873