[unsavedhero]

I know how to write the condensed electron configuration for elements in the s p and d blocks however, i get lost on the f block elements. the condensed electron configuration for uranium is [Rn] 5f3 6d1 7s2. i have no idea how they got that.. i know that the n of f block elements is 2 lower than the period they're in but the order makes no sense. ive done hours of research