“…Sun and M. Zhang [11] also answered Selfridge's question. Actually, there are fourteen such pairs which are solution of Selfridge's question and they are (1,0), (2,1), (3,1), (4,2), (5,1), (5,3), (6,2), (7,3), (8,2), (8,4), (9,3), (14,2), (15,3) and (16,4). Once Selfridge's question is answered completely, a natural question arises: what happens if we replace '2' by '3' or more generally by some other integer (other than ± 1).…”