Not sure what kind of maths but I think its summination

Hey also dont know if this is the right section of the forum but I guess an admin can move it and tell me where it is.

http://www.math.ucdavis.edu/%7Ekouba...ctory/img5.gif

http://www.math.ucdavis.edu/%7Ekouba...ctory/img7.gif

If you look at the nth formula for these you can see it is squared in the 2nd formula. I don't think its a random occurrence and my maths teacher also doesn't know why its like that. Do any of you and can you prove why?