Clarke’s book The Lost Worlds of 2001 goes into a lot of detail about the process (and is a great read in its own right). His take was that the book should say “a novel by Arthur C Clarke, based on the screenplay by Stanley Kubrick” and the movie should say “screenplay by Stanley Kubrick, based on the novel by Arthur C Clarke”.

I think Kubrick was very much the dominant force in the partnership, but they did work quite closely together.