Date: Dec 25, 2012 7:35 PM
Author: thomasinventions@yahoo.com
Subject: Blankenhorn-Ramanujan Ellipse circumference formula

Added improvement to the Blankenhorn-Ramanujan ellipse circumference formula with easier to memorize numbers:

C~pi(a+b)*(1+3h/(10+sqrt(4-3h)) +(1.5*h^6-0.5*h^12)/((11pi/(44-14pi))+24100(1-h)))

Where a and b are the half length axes and h = (a-b)^2/(a+b)^2

Referencing http://i39.photobucket.com/albums/e191/toomers/ell1.jpg, replace the h^5.20114 with 1.5*h^6-0.5*h^12, and the 19176 with 24100.

See: http://ellipse-circumference.blogspot.com