Modelling Chaos theory help

Dear all,

I am relatively new to mathcad and could do with some help solving the errors that i have encountered.

I am trying to model the equation

x(subscript:n+1) = r*x(subscipt n) - x(subscipt n) ^3 where 0<r<3 and n is an integer 1-1000.

I believe this should output a bifurcation however i can not seem to get the program to output anything with a variable r, when r is a constant i get a chaos graph but i would like to plot x wrt r. If anyone has got any advice it would be greatly appreciated. I have attatched the work i have done i apologise for it being messy