<s>[INST] This problem involves a combination of mathematical thinking and programming. We have a set of numbers that is defined by the following rule: a set contains all integers from 1 to N, where N is a positive integer, and each number appears at least once. However, there is an interesting property of this set, which is that the sum of any two elements in the set is greater than the sum of any one element and the number of elements (N+1). In other words, for any two numbers x and y in the set, x+y>N+1. 

Now, we need to find the maximum possible value of N for a set of a given size. We can think of it as finding the maximum value of N such that the set {1, 2, ..., N} satisfies the property.

Given the size of the set (let's call it n), can you write a program to find the maximum possible value of N?[/INST]