OFFSET
0,3
COMMENTS
Hankel transform is A134751.
FORMULA
G.f.: 1/(1-x-2x^2/(1-2x^2/(1-x-x^2/(1-2x^2/(1-x-2x^2/(1-x^2/(1-x-2x^2/(1-... (continued fraction).
G.f.: (1-x-3x^2-sqrt((1-3x-7x^2+19x^3+15x^4-25x^5-16x^6)/(1-x)))/(2x^2(1-x-2x^2)).
Conjecture: (n+2)*a(n) +5*(-n-1)*a(n-1) +2*(-n+3)*a(n-2) +(38*n-59)*a(n-3) +(-22*n+41)*a(n-4) +4*(-22*n+81)*a(n-5) +3*(19*n-79)*a(n-6) +3*(29*n-164)*a(n-7) +2*(-17*n+98)*a(n-8) +16*(-2*n+15)*a(n-9)=0. - R. J. Mathar, Oct 08 2016
MATHEMATICA
CoefficientList[Series[(1-x-3x^2-Sqrt[(1-3x-7x^2+19x^3+15x^4-25x^5-16x^6)/(1-x)])/(2x^2(1-x-2x^2)), {x, 0, 40}], x] (* Harvey P. Dale, Mar 04 2011 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul Barry, Feb 18 2011
STATUS
approved