This is technically true probably should say something showing how when j=N-1 the second argument is N to be more thorough.

This is technically true probably should say something showing how when j=N-1 the second argument is N to be more thorough.

Well, it should be clear that since the term j=N-1 remains, and i iterates range [1, N], opt(k, N) form should make clear sense. Saying j=N is a lot more confusing, since the positive term is "opt(i+1, j+1)", not "opt(i, j)", where j=N makes sense, but it isn't the positive term and people can easily misinterpret for the negative term. Though I don't think more explanation is needed, since positive term should clearly refer to "opt(i+1, j+1)" where j=N-1 is correct. Plus j cannot be N because j iterates range [i, N-1].

You're right. I guess I'd prefer to add an additional line but surely it's not more wrong than what's already there.