Genetic algorithms - repeated values

My function A produces same values repeatedly even though using different variables (assuming that they are all correct answers and there is no error here). E.g out of 1,000 points produced, 6,000 points are repeated values. When I run GA, this will burden the algorithms to optimize my function. How can I program in such a way that GA will skip the repeated points during the crossover operation? How can I handle the repeated values in my function? How to filter the same values?

[David Barry]

I don't really understand the question. Out of 1000 produced points, 6000 are repeated? Can you include some example code.