%I
%S 1,1,1,1,2,4,9,21,51,127,323,835,2188,5798,15511,41835,
%T 113634,310572,853467,2356779,6536382,18199284,50852019,
%U 142547559,400763223,1129760415,3192727797,9043402501,25669818476,73007772802
%N Expansion of (1  x + sqrt(1  2*x  3*x^2))/2 in powers of x.
%C Apart from a(1) the same as A168051.  _R. J. Mathar_, Sep 18 2017
%F Convolution inverse of A001006.
%F Let f(x) = (1  x  sqrt(1  2*x  3*x^2))/(2*x^2).
%F G.f.: 1xx^2/(1xx^2/(1xx^2/(1xx^2/(1xx^2/(... (continued fraction).
%F G.f.: 1/f(x) = 1  x  x^2*f(x).
%F a(n) = A001006(n2) for n > 1.
%Y Cf. A001006, A086246.
%K sign
%O 0,5
%A _Seiichi Manyama_, Sep 16 2017
