Are those 3 number sequences for obverse & reverse (a) on the same type of chip, or (b) on chips from 3 different casinos (or 3 different denom from same casino)?

Just a couple of guesses:

If (a): Numbered at 2 different stages of the manufacturing process. Each may be a consecutive number, but if all jetons finished and numbered on side A, then jumbled in a box, and finished & numbered on side B, the side A / side B numbers would not have any particular relationship to each other, except for the lower and upper limits boundaries.

If (b): The first number is a batch number (which remains the same for each batch) and the second number is a consecutive number for each chip.

To infer further, you'd need a larger number of samples of the same jeton to make further deductions.