\[ \boxed { {x}^{2}{\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) +ax{\frac {\rm d}{{\rm d}x}}y \left ( x \right ) +by \left ( x \right ) =0} \]
Mathematica: cpu = 0.011001 (sec), leaf count = 99 \[ \left \{\left \{y(x)\to c_1 x^{\frac {1}{2} \sqrt {b} \left (-\frac {\sqrt {a^2-2 a-4 b+1}}{\sqrt {b}}-\frac {a-1}{\sqrt {b}}\right )}+c_2 x^{\frac {1}{2} \sqrt {b} \left (\frac {\sqrt {a^2-2 a-4 b+1}}{\sqrt {b}}-\frac {a-1}{\sqrt {b}}\right )}\right \}\right \} \]
Maple: cpu = 0.015 (sec), leaf count = 53 \[ \left \{ y \left ( x \right ) ={\it \_C1}\,{x}^{-{\frac {a}{2}}+{\frac { 1}{2}}+{\frac {1}{2}\sqrt {{a}^{2}-2\,a-4\,b+1}}}+{\it \_C2}\,{x}^{-{ \frac {a}{2}}+{\frac {1}{2}}-{\frac {1}{2}\sqrt {{a}^{2}-2\,a-4\,b+1}} } \right \} \]