CS320 Homework 1

Given a sorted sequence of positive integers, add these such that the smallest numbers, including intermediate results, are added together.

       Example 

          sequence     1 2 2 2 5 6
          additions:   1+2
                       2+2
                       3+4
                       5+6
                       7+11

A lower bound of this problem is Ω(n).

Is this a closed problem? Provide a solid argument.