\[ -\left (2 a x^2+1\right ) y'(x)+b x^3 y(x)+x y''(x)=0 \] ✓ Mathematica : cpu = 0.0109047 (sec), leaf count = 91
\[\left \{\left \{y(x)\to c_1 e^{\frac {1}{2} \sqrt {b} x^2 \left (\frac {a}{\sqrt {b}}-\frac {\sqrt {a^2-b}}{\sqrt {b}}\right )}+c_2 e^{\frac {1}{2} \sqrt {b} x^2 \left (\frac {\sqrt {a^2-b}}{\sqrt {b}}+\frac {a}{\sqrt {b}}\right )}\right \}\right \}\] ✓ Maple : cpu = 0.147 (sec), leaf count = 45
\[ \left \{ y \left ( x \right ) ={\it \_C1}\,{{\rm e}^{{\frac {{x}^{2}}{2} \left ( \sqrt {{a}^{2}-b}+a \right ) }}}+{\it \_C2}\,{{\rm e}^{-{\frac {{x}^{2}}{2} \left ( \sqrt {{a}^{2}-b}-a \right ) }}} \right \} \]