Designing a sweater pattern

Somewhere on the internet I has seen a formula for designing a sweater pattern with any yarn for any size. The formula is simple. Can someone help me find where that website is? I have googled, but come up empty. I am sure it is there somewhere.

This one?

Yes, thanks so much. This is one I was looking for. I think there is another one also.

There are an insane number of calculators here as well: