Thank you for that little trick. Even if it doesn't matter for this case I will remember it for later. I know I've read stuff like that before, but I haven't learned enough of that part of discrete math to really understand why (but it seems kind of intuitive).
As a coincidence I got "A Concrete Introduction to Higher Algebra" by Lindsay Childs in the mail today. The concrete part of the book is that he uses properties about integers to introduce and teach concepts about algebra (and then he goes on to polynomials and other stuff). So now I got no excuse to not know that stuff any longer :-).
As a coincidence I got "A Concrete Introduction to Higher Algebra" by Lindsay Childs in the mail today. The concrete part of the book is that he uses properties about integers to introduce and teach concepts about algebra (and then he goes on to polynomials and other stuff). So now I got no excuse to not know that stuff any longer :-).