What is the firing order on a straight six?

A Ford Inline-6 is 1-5-3-6-2-4 Here is an easy way for a MAN to remember it. I hope I dont offend anyone but 15 is to young 36 is to old and 24 is just right.(153624) Get it?

The other theoretical possibilities are 1-2-4-6-5-3 and 1-5-4-6-2-3.