MAIO is applied to same timeslot of different TRX (belonging to a same cell). For instance, each timeslot #3 will have a different MAIO, because they’re using the same HSN.
If all timeslot #3 have the same HSN (=sequence), they need to start their sequence at different frequencies, so they don’t run the same “pseuo random” sequence at the same moment. The MAIO will “offset” the sequence for each timeslot.
The “pseudo random” property means it will perform a sequence that looks random, but that in fact is not : the sequence of frequencies is fixed, and will keep repeating itself after one run.