OFFSET
1,3
COMMENTS
For an introduction to reductions of polynomials by substitutions such as x^2->x+2, see A192232.
FORMULA
Empirical G.f.: -x^2*(x+1)*(2*x-1)/((x^2+2*x-1)*(4*x^2+2*x-1)). [Colin Barker, Nov 13 2012]
MATHEMATICA
(See A192338.)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Jun 28 2011
STATUS
approved