✓ Mathematica : cpu = 0.259099 (sec), leaf count = 38
DSolve[Derivative[2][y][x] == -(((a*(1 + a) - a*(3 + a)*x^2)*y[x])/(x^2*(-1 + x^2))) + (2*x*Derivative[1][y][x])/(-1 + x^2),y[x],x]
✓ Maple : cpu = 0.047 (sec), leaf count = 33
dsolve(diff(diff(y(x),x),x) = 2*x/(x^2-1)*diff(y(x),x)-(a*(a+1)-a*x^2*(a+3))/x^2/(x^2-1)*y(x),y(x))