Implementing a programming idea of random numbers and arrays
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I am kind of new in programming generally and I found it a good idea to ask here first.

So, let's say I have about 900 sets of 6 numbers stored somewhere (maybe in arrays?). I want each time to generate a random set of 6 numbers that is different than the other 900. If it is the same (check with the other 900), then don't accept it and generate a new. I thought of using arrays and check the new set with the others each time, but I think it's a little "painful" to have 900 arrays before.

Any ideas would be appreciated! Thanks!