I've tried my best to search for an answer myself, but it's been a decade and a half since I last sat in a classroom and unfortunately it seems I no longer possess the adequate nomenclatural vernacular to properly phrase my question via search engine/SE.
Question
I am trying to mathematically express — in answer to someone's written inquiry, not a mathematical/formulaic problem — that "the outcomes can possibly be 0, 2, 4, or 6".
Uneducated Guess
0–6 Δ++2?
Context
For product specification documentation in my occupational industry, I am familiar with tolerance ranges being expressed as, e.g., 30g ±2g meaning "30 grams with a maximum expected deviation range of plus-or-minus 2 grams. However, we've never had to express this with an implication that the range consists of incremental/decremental deltas. So in the end, I began to wonder: how would the mathematical communities or academia notate this? And do professional/industrial settings conform to the same formatting convention(s)? Please note that my question above is not specific to any unit of measure.
Optional Reading
Semi-related anectdote: I'm not sure if this is unique to the food safety discipline or not, but when given non-symmetrical bounds for (and/or multiple potential sources of) deviations, we use the greater or cumulative figure — or depending on the context, the figure that represents greater accepted "risk", which is defined and quantified as the product of severity and likelihood. So in the above contextual example, we account for not just product physical properties via challenge study and trending assessment (i.e., product hypothetically comes out between 28.5g – 31.5g) but also equipment weight scales' calibration certificate accuracy tolerance (±0.5g). I've never actually verified whether there's a more syntactically proper representation of this or not from a mathematics perspective.