OFFSET
0,1
LINKS
I. Reiten, Dynkin diagrams and the representation theory of algebras, Notices of the AMS, Vol. 44, No 5 (1997) 546-556. [MR1444112]
FORMULA
a(n) = 7*(n+1) + 2*A087866(n).
G.f.: (7/(1-x)^2) + 2*(1-x^15)/((1-x^6)*(1-x^10)*(1-x)).
MATHEMATICA
CoefficientList[ Series[ (9-2x+9x^3-2x^4+9x^5-2x^7+9x^8) / (1-2x+x^2+x^3-2x^4+2x^5-2x^6+x^7+x^8-2x^9+x^10), {x, 0, 54}], x] (* Jean-François Alcover, Dec 02 2011 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Boddington, Jan 22 2004
STATUS
approved