\[ y''(x)=-\frac {\left (a+3 x^2\right ) y'(x)}{x^3}-\frac {b y(x)}{x^6} \] ✓ Mathematica : cpu = 0.0137593 (sec), leaf count = 56
\[\left \{\left \{y(x)\to e^{\frac {a-\sqrt {a^2-4 b}}{4 x^2}} \left (c_1 e^{\frac {\sqrt {a^2-4 b}}{2 x^2}}+c_2\right )\right \}\right \}\]
✓ Maple : cpu = 0.09 (sec), leaf count = 45
\[ \left \{ y \left ( x \right ) ={\it \_C1}\,{{\rm e}^{-{\frac {1}{4\,{x}^{2}} \left ( -a+\sqrt {{a}^{2}-4\,b} \right ) }}}+{\it \_C2}\,{{\rm e}^{{\frac {1}{4\,{x}^{2}} \left ( a+\sqrt {{a}^{2}-4\,b} \right ) }}} \right \} \]