Decomposition of rationnal fractions



Hi.

Is there any way to obtain the decomposition in simple elements (don't
know exactly how to say this in english) of a fraction of the form :

          1
  -------------------
  (1-X)(1-X^2)(1-X^5)

(to obtain its formal series equivalent \sum a_nX^n, a_n being the
number of ways to pay n? using 1, 2 and 5? corners (no, there
is no such thing as a 5? corner, but there's a 5? banknote !)).

I'd like to obtain the C-decomposition, what do I have to do ?

\bye

-- 

Nicolas FRANCOIS                      |  /\ 
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