How Do You Know What's Going On?

We're just going up by one each number. What is the fourth overtone of a sea at a hundred 30 hurts? 130 times five, 680. Sing 220 by three does not give us the same note. So it's good to get in these kind ties if we can weave ourselves out of them,. Because when we do, we just get surer. And sure of what, this mathematical structure, this is built round.