It is simple as Pi.
This is a TN message board however.
Do you mean that it is very easy for a canadian citizen to get F1 visa even if he/she has to pay everything by him/herself?
What does Pi mean?
If anything, that would make it easier - assuming you can demonstrate the financial ability to do so. Besides, there's no visa needed - just show up at the border with your I-20.
I take it from that answer that you are not seeking a graduate degree in Mathematics.