\[ -a x^3 y(x)-y'(x)+x y''(x)=0 \] ✓ Mathematica : cpu = 0.007001 (sec), leaf count = 41
\[\left \{\left \{y(x)\to c_1 \cosh \left (\frac {\sqrt {a} x^2}{2}\right )+i c_2 \sinh \left (\frac {\sqrt {a} x^2}{2}\right )\right \}\right \}\] ✓ Maple : cpu = 0.035 (sec), leaf count = 27
\[ \left \{ y \left ( x \right ) ={\it \_C1}\,\sinh \left ( {\frac {{x}^{2}}{2}\sqrt {a}} \right ) +{\it \_C2}\,\cosh \left ( {\frac {{x}^{2}}{2}\sqrt {a}} \right ) \right \} \]