\[ \boxed { {\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) =-{\frac {a{x}^{2\,a-1}{\frac {\rm d}{{\rm d}x}}y \left ( x \right ) }{{x}^{2\,a}}}-{\frac {{b}^{2}y \left ( x \right ) }{{x}^{2\,a}}}=0} \]
Mathematica: cpu = 0.023003 (sec), leaf count = 43 \[ \left \{\left \{y(x)\to c_1 \cos \left (\frac {b x^{1-a}}{a-1}\right )-c_2 \sin \left (\frac {b x^{1-a}}{a-1}\right )\right \}\right \} \]
Maple: cpu = 0.016 (sec), leaf count = 39 \[ \left \{ y \left ( x \right ) ={\it \_C1}\,\sin \left ( {\frac {{x}^{1-a} b}{a-1}} \right ) +{\it \_C2}\,\cos \left ( {\frac {{x}^{1-a}b}{a-1}} \right ) \right \} \]