\[ x^4 y''(x)+\left (x y'(x)-y(x)\right )^3=0 \] ✓ Mathematica : cpu = 0.269586 (sec), leaf count = 104
DSolve[(-y[x] + x*Derivative[1][y][x])^3 + x^4*Derivative[2][y][x] == 0,y[x],x]
\[\left \{\left \{y(x)\to -i x \log \left (\frac {\frac {e^{c_2}}{x}-\frac {\sqrt {e^{2 c_2}-8 i c_1 x^2}}{x}}{4 c_1}\right )\right \},\left \{y(x)\to -i x \log \left (\frac {\frac {\sqrt {e^{2 c_2}-8 i c_1 x^2}}{x}+\frac {e^{c_2}}{x}}{4 c_1}\right )\right \}\right \}\] ✓ Maple : cpu = 0.949 (sec), leaf count = 37
dsolve(x^4*diff(diff(y(x),x),x)+(x*diff(y(x),x)-y(x))^3=0,y(x))
\[y \left (x \right ) = \left (-\arctan \left (\frac {1}{\sqrt {c_{1} x^{2}-1}}\right )+c_{2}\right ) x\]