Find nontrivial solutions to other than , where is the divisor function. Nontrivial solutions means that solutions which are multiples of smaller solutions are not considered. For example, multiples of are solutions for , 7, 9, 11, 13, 17, 19, 23, 21, ....
Nontrivial solutions to Wallis's equation include , (326, 407), (406, 489), (627, 749), (740, 878), (880, 1451), (888, 1102), (1026, 1208), (1110, 1943), (1284, 1528, 1605), (1510, 1809), (1628, 1630, 2035), (1956, 2030, 2445), (2013, 2557), (2072, 3097), (2508, 2996, 3135, 3745), ....