31 Jul
2006
31 Jul
'06
12:34 p.m.
Here are the first 20 terms of a sequence: 1,2,6,12,60,3,21,168,504,2520,27720,4,52,364,5460,21840,371280,1113840,21 162960,5 The puzzle is to determine the rule of formation. Franklin T. Adams-Watters