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%I #7 Jan 30 2018 18:57:36
%S 8,14,20,26,32,38,44,48,52,56,60,62,64,64,64,64,64,62,60,56,52,48,44,
%T 38,32,26,20,14,8,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%U 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%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.
%K easy,nonn
%O 0,1
%A _Paul Boddington_, Jan 22 2004
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