\[ \boxed { {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) -{\it a3}\, \left ( y \left ( x \right ) \right ) ^{3}-{\it a2}\, \left ( y \left ( x \right ) \right ) ^{2}-{\it a1}\,y \left ( x \right ) -{\it a0}=0} \]
Mathematica: cpu = 0.051007 (sec), leaf count = 54 \[ \text {Solve}\left [\text {RootSum}\left [\text {$\#$1}^3 \text {a3}+\text {$\#$1}^2 \text {a2}+\text {$\#$1} \text {a1}+\text {a0}\& ,\frac {\log (y(x)-\text {$\#$1})}{3 \text {$\#$1}^2 \text {a3}+2 \text {$\#$1} \text {a2}+\text {a1}}\& \right ]=c_1+x,y(x)\right ] \]
Maple: cpu = 0.016 (sec), leaf count = 30 \[ \left \{ x-\int ^{y \left ( x \right ) }\! \left ( {{\it \_a}}^{3}{\it a3 }+{{\it \_a}}^{2}{\it a2}+{\it \_a}\,{\it a1}+{\it a0} \right ) ^{-1}{d {\it \_a}}+{\it \_C1}=0 \right \} \]
Sage: cpu = 0.228 (sec), leaf count = 0 \[ \left [\int \frac {1}{a_{3} y\left (x\right )^{3} + a_{2} y\left (x\right )^{2} + a_{1} y\left (x\right ) + a_{0}}\,{d \left (y\left (x\right )\right )} = c + x, \text {\texttt {separable}}\right ] \]