(-3,-2,-1), (-1,0,1) & (1,2,3) have the properties that you mentioned in the question.
The present ages of A,B and C are in proportions 3:4:5. Six years ago, the sum of their ages was 54. What is the product of their ages?
If a + b + c = 8 a.b.c = 27 then Is there exist solution/s in (a,b,c) where a, b and c are positive real numbers?
If 1^3 + 2^3 + 3^3 = m^2 where m is also an integer. What are the next three consecutive positive integers such that the sum of their individual cubes is equal to a perfect square?
If a, b, c and d are distinct pairwise co-prime positive integers such that a^2 + b^2 = c^2 + d^2, find the lowest possible value of a + b + c + d?