%N Poincaré series [or Poincare series] of the preprojective algebra of a Dynkin diagram of type E_8.
%D I. Reiten, Dynkin diagrams and the representation theory of algebras, Notices of the AMS, Vol. 44, Number 5.
%e The series is a polynomial because the algebra is finite dimensional. For an arbitrary Dynkin diagram the corresponding polynomial is (n+n*x^h-2*x^e_1-...-2*x^e_n)/(1-x)^2, where n is the rank, h the Coxeter number and e_1,...,e_n the Coxeter exponents of the associated Coxeter group.
%Y Cf. A089010, A091571, A091572, A091573, A091574, A091576, A091577.
%A _Paul Boddington_, Jan 22 2004