A little nitpick:
> И indicates a digital circuit, while ИЕ is a counter
digital circuits were not only [И-], this prefix means arithmetic and register-based circuits. Because there were a lot more “digital” circuits starting with [Л-] (L- means Logic), [A-] for transmission gates and bus arbiters. [B-] for microprocessors and related stuff, [Р-] for memory, etc... The almost complete list can be found here: https://electronics.fandom.com/ru/wiki/%D0%9E%D0%B1%D0%BE%D0...
