\[ \left (x^2-1\right ) y''(x)+\left (x^2+1\right ) y(x)+4 x y'(x)=0 \] ✓ Mathematica : cpu = 0.0305694 (sec), leaf count = 45
\[\left \{\left \{y(x)\to \frac {c_1 e^{-i x}}{x^2-1}-\frac {i c_2 e^{i x}}{2 \left (x^2-1\right )}\right \}\right \}\]
✓ Maple : cpu = 0.438 (sec), leaf count = 27
\[ \left \{ y \left ( x \right ) ={\frac {{\it \_C1}\,\sin \left ( x \right ) }{{x}^{2}-1}}+{\frac {{\it \_C2}\,\cos \left ( x \right ) }{{x}^{2}-1}} \right \} \]