OFFSET
0,4
COMMENTS
Hankel transform is A178115.
FORMULA
D-finite with recurrence: +(n+2)*a(n) +2*(-n-1)*a(n-1) +(7*n-4)*a(n-2) +2*(-3*n+4)*a(n-3) +5*(n-2)*a(n-4)=0. - R. J. Mathar, Feb 10 2015
MATHEMATICA
CoefficientList[Series[(Sqrt[1-2x+7x^2-6x^3+5x^4]-(1-x+x^2))/(2x^2 (1-x+x^2)), {x, 0, 40}], x] (* Harvey P. Dale, Dec 01 2013 *)
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Paul Barry, May 20 2010
STATUS
approved