Nana your work is very impressive, that last equation is wonderful, that's the sort of mathematical relationship that I always enjoy thinking about. Did you notice how it has multiplication, addition, and exponentiation all in one? Random fact but Richard P. Feynman said that he thought the most elegant equation was e^(i*pi) + 1 = 0 for similar reasons.
Hm, I think this is correct, but I don't have the time right now to analyze it. I grouped terms up, the MSRPs are a through j, a>b>c>d....>j. Here is the first few terms, a + b - a/3 + c - b/3 - a/9 + d - c/3 - b/9 - a/27, and so on, and the last price looks like this j - i/3 - h/9 - g/27 - f/81 - e/243 - d/729 - c/287 - b/6561 - a/19683. not very elegant right?
Here's the final price all tidied up, on first glance it seems like its a bigger discount than i imagined so i think its wrong, but i think i am on the right track: a*9842/19683 + b*3281/6561 + c*1094/2187 + d*365/729 + e*122/243 + f*41/81 + g*14/27 + h*5/9 + i*2/3 + j. Nana7 maybe you can finish it up? Did I make any glaring errors?