\[ \left (y(x)-x^2\right ) y'(x)+4 x y(x)=0 \] ✓ Mathematica : cpu = 0.0993618 (sec), leaf count = 257
\[\left \{\left \{y(x)\to x^2+\frac {1}{-\frac {1}{2 x^2}-\frac {\frac {1}{2}-\frac {i}{2}}{\sqrt {2} x^2 \sqrt {x^2 \sinh \left (\frac {2 c_1}{9}\right )+x^2 \cosh \left (\frac {2 c_1}{9}\right )-i}}}\right \},\left \{y(x)\to x^2+\frac {1}{-\frac {1}{2 x^2}+\frac {\frac {1}{2}-\frac {i}{2}}{\sqrt {2} x^2 \sqrt {x^2 \sinh \left (\frac {2 c_1}{9}\right )+x^2 \cosh \left (\frac {2 c_1}{9}\right )-i}}}\right \},\left \{y(x)\to x^2+\frac {1}{-\frac {1}{2 x^2}-\frac {\frac {1}{2}+\frac {i}{2}}{\sqrt {2} x^2 \sqrt {x^2 \sinh \left (\frac {2 c_1}{9}\right )+x^2 \cosh \left (\frac {2 c_1}{9}\right )+i}}}\right \},\left \{y(x)\to x^2+\frac {1}{-\frac {1}{2 x^2}+\frac {\frac {1}{2}+\frac {i}{2}}{\sqrt {2} x^2 \sqrt {x^2 \sinh \left (\frac {2 c_1}{9}\right )+x^2 \cosh \left (\frac {2 c_1}{9}\right )+i}}}\right \}\right \}\]
✓ Maple : cpu = 0.178 (sec), leaf count = 53
\[ \left \{ y \left ( x \right ) =-{\frac {{\it \_C1}}{2} \left ( -{\it \_C1}+\sqrt {{{\it \_C1}}^{2}-4\,{x}^{2}} \right ) }-{x}^{2},y \left ( x \right ) ={\frac {{\it \_C1}}{2} \left ( {\it \_C1}+\sqrt {{{\it \_C1}}^{2}-4\,{x}^{2}} \right ) }-{x}^{2} \right \} \]