Problem
ALG-B2-M01-P004 Distinct positive integers
#4
★★★☆☆ Level 3 of 5
Let \(A\) be a set of \(n\) distinct positive integers. Prove that the sum of the elements of \(A\) is at least \(\frac{n(n+1)}2\).
Hint 1. Arrange the numbers in increasing order.
Hint 2. The smallest possible sequence is \(1,2,\ldots,n\).
Write the elements as \(a_1
Module training problem. Method tags: ordering, bounds.