@Pecoflyer #2

{1,2,3,4,5}, {1,2,3,4}, {1,2,3}...

Why? It is to cater for the case where there are only 4, 3, 2 or even 1 numbers (not 5).

But now your expression appears to be more precise. Thanks for your idea, which inspires me to how to make codes simpler.