boost converter

Does anyone know how you calculate the inductance, capacitance etc for continuous inductor current for a 3-stage boost converter? Are the equations the same as for a single boost converter?
Does anyone know if it is normal practice to cascade boost converters? I am trying to step up a 12 V dc voltage to 340V

I made a 9 volt to 100 volt boost converter using the LTC1872. The data sheet has the info you are looking for.