sympy.physics.continuum_mechanics.beam wrong results

[faradai2008]

I think there is a problem with the Beam module when using a force with an order bigger than 1.
This is an example where R should be 1/3 and remains constant when changing the length of the beam, but unfortunately it's not the case.
I believe it has to do with the formation of the load equation, where the higher order compensation isn't been taken into consideration.