There is a problem here, old chap. Basically, unless you can prove that it is impossible to generate a pseudorandom sequence which does not repeat, you have to accept the possibility of it repeating. If the federal standard whatever says otherwise, it is incorrect. I think that one MUST accept the possibility of a non-repeating pseudorandom sequence. Consider counting with unbounded arbitrary size integers, and feeding them into a hash function. The sequence never repeats.
Cleanup? Yes. Merge? No.
1. Pseudo-random sequence is finite by definition, so, it "repeats". 2. Terms are mixed here. Pseudo-random sequences are not necessarily sequences of 0's and 1's. The latter ones are called pseudo-random binary sequences or PRBS's. 3. The number of 0's and 1's are not necessarily about the same. Those with about equal number of 0's and 1's have a duty cycle of 1/2 but duty cycle can be other than one-half, ranging between 0 and 1.