Okay so we have to define some variables here.
CR = the number of links we have at our current rank
DR = the number of links our desired rank has
NL = the number of no follow links to improve our ranking
LV = the actual SEO link value of a nofollow link, which is a constant value that is equal to zero.
The formula is:
NL=(DR - CR)*(1/LV)
Once you have attempt to do this calculation, then you will completely understand no-follow links. This formula has been known about since 2005.
This concludes today's lesson in SEO math.