\[ y''(x)=\frac {2 x y'(x)}{x^2-1}-\frac {y(x) \left (\left (x^2-1\right ) x^2 (a-n) (a+n+1)+2 a x^2+n (n+1) \left (x^2-1\right )\right )}{x^2 \left (x^2-1\right )} \] ✗ Mathematica : cpu = 10.2771 (sec), leaf count = 0 , DifferentialRoot result
\[\left \{\left \{y(x)\to (x)\right \}\right \}\]
✓ Maple : cpu = 0.231 (sec), leaf count = 109
\[\left \{y \left (x \right ) = c_{1} x^{-n} \HeunC \left (0, -n -\frac {1}{2}, -2, -\frac {1}{4} a^{2}+\frac {1}{4} n^{2}-\frac {1}{4} a +\frac {1}{4} n , \frac {1}{4} a^{2}-\frac {1}{4} n^{2}-\frac {1}{4} a -\frac {1}{4} n +\frac {3}{4}, x^{2}\right )+c_{2} x^{n +1} \HeunC \left (0, n +\frac {1}{2}, -2, -\frac {1}{4} a^{2}+\frac {1}{4} n^{2}-\frac {1}{4} a +\frac {1}{4} n , \frac {1}{4} a^{2}-\frac {1}{4} n^{2}-\frac {1}{4} a -\frac {1}{4} n +\frac {3}{4}, x^{2}\right )\right \}\]