\[ y(x) \left (x^2 \left (a+f'(x)+f(x)^2\right )-(v-1) v\right )+2 x^2 f(x) y'(x)+x^2 y''(x)=0 \] ✓ Mathematica : cpu = 0.0428519 (sec), leaf count = 98
\[\left \{\left \{y(x)\to c_1 J_{\frac {1}{2} (2 v-1)}\left (\sqrt {a} x\right ) \exp \left (\int _1^x\frac {1-2 f(K[1]) K[1]}{2 K[1]}dK[1]\right )+c_2 Y_{\frac {1}{2} (2 v-1)}\left (\sqrt {a} x\right ) \exp \left (\int _1^x\frac {1-2 f(K[1]) K[1]}{2 K[1]}dK[1]\right )\right \}\right \}\] ✓ Maple : cpu = 0.078 (sec), leaf count = 40
\[ \left \{ y \left ( x \right ) =\sqrt {x}{{\rm e}^{-{\frac {\int \!2\,f \left ( x \right ) \,{\rm d}x}{2}}}} \left ( {{\sl Y}_{v-{\frac {1}{2}}}\left (\sqrt {a}x\right )}{\it \_C2}+{{\sl J}_{v-{\frac {1}{2}}}\left (\sqrt {a}x\right )}{\it \_C1} \right ) \right \} \]