\[ f(x) \left (x^2 y''(x)-2 x y'(x)+2 y(x)\right )+y^{(3)}(x)=0 \] ✓ Mathematica : cpu = 0.0945188 (sec), leaf count = 88
\[\left \{\left \{y(x)\to c_3 x \left (\int _1^x\frac {\exp \left (-\int _1^{K[2]}f(K[1]) K[1]^2dK[1]\right )}{K[2]^2}dK[2]-x \int _1^x\frac {\exp \left (-\int _1^{K[3]}f(K[1]) K[1]^2dK[1]\right )}{K[3]^3}dK[3]\right )+c_2 x^2+c_1 x\right \}\right \}\] ✓ Maple : cpu = 0.397 (sec), leaf count = 33
\[ \left \{ y \left ( x \right ) = \left ( \int \!{\it \_C1}+{\it \_C2}\,\int \!{{\rm e}^{-\int \!{x}^{2}f \left ( x \right ) +3\,{x}^{-1}\,{\rm d}x}}\,{\rm d}x\,{\rm d}x+{\it \_C3} \right ) x \right \} \]