It was confusing for me too, which is why I gave an imperative definition: first form the union of I and J, then merge any overlapping elements. Did that not help?
It should have. The fault is certainly mine. I skimmed your definition too lightly because you were defining a technical term (“meet”) in a context (partitions) where I was already familiar with the term, but I hadn’t suspected that it had any other usages than the one I knew.
It was confusing for me too, which is why I gave an imperative definition: first form the union of I and J, then merge any overlapping elements. Did that not help?
It should have. The fault is certainly mine. I skimmed your definition too lightly because you were defining a technical term (“meet”) in a context (partitions) where I was already familiar with the term, but I hadn’t suspected that it had any other usages than the one I knew.