OFFSET
1,3
REFERENCES
Fouad Ibn-Majdoub-Hassani. Combinatoire de polyominos et des tableaux decales oscillants. These de Doctorat, Laboratoire de Recherche en Informatique, Universite Paris-Sud XI, France.
FORMULA
G.f.: (x*(1-4*x+6*x^2-3*x^3+x^4))/((1-x)*(1-3*x+x^2)^2)
MATHEMATICA
Join[{1, 0}, Take[CoefficientList[Series[(q*(1 - 4*q + 6*q^2 - 3*q^3 + q^4))/((1 - q)*(1 - 3*q + q^2)^2), {q, 0, 27}], q], -26]]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Fouad IBN MAJDOUB HASSANI, Apr 14 2003
EXTENSIONS
More terms from Robert G. Wilson v, Apr 15 2003
STATUS
approved