Constructive.
To prove that there is a positive integer that equals the sum
of the positive integers not exceeding it.
A plain and simple example is
1.1 + 2 = 3
2.10 + 50 +
100 =160
3.6x + 8x +
2x = 16 x
Notice that the sum of the numbers is always greater than the
addends. This only proves that any positive sum of any two positive addends
will not compare and thus the addends not exceeding a greater value than the
sum.