If you have 3 specific numbers in mind for the first three, you can run another 3/49 program list with IF - THEN - ELSE qualfiers to eliminate the specified numbers and arrive at a list of 15,180 possibilities. If you don't have any specific numbers in mind, you can run a 3/49 listing followed by another 3/49 listing with IF - THEN - ELSE qualifiers but each six-number combination will be listed 20 times, and I don't think that's what you're looking for. I don't have anything in my program list, and I really don't know where to direct you for your specific application.
gl
john