OFFSET
0,1
REFERENCES
I. Reiten, Dynkin diagrams and the representation theory of algebras, Notices of the AMS, Vol. 44, Number 5.
EXAMPLE
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.
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Boddington, Jan 22 2004
STATUS
approved