[R] Proper way to typeset the symbol for R in LaTeX?

[Charilaos Skiadas]

Hoping this is not off topic...

I am in the process of writing some tutorials for my students for  
learning R, and naturally I'm using Sweave for this. So suddenly a  
question occurred to me: LaTeX has a recommended way of typesetting  
the TeX and LaTeX symbols, via the \TeX and \LaTeX commands. Is there  
a similar command for the R symbol, or in general are there any  
guidelines/recommendations on how to typeset the letter R when  
referring to the  R language?

Haris