 Open problems in the study of these maps still remain.From the second "n"-tuple onwards, it is clear that every integer in each "n"-tuple in a Ducci sequence is greater than or equal to 0 and is less than or equal to the difference between the maximum and minimum members of the first "n"-tuple.As there are only a finite number of possible "n"-tuples with these constraints, the sequence of n-tuples must sooner or later repeat itself.