\[ \boxed { {\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) -2\, \left ( y \left ( x \right ) \right ) ^{3}-xy \left ( x \right ) +a=0} \]
Mathematica: cpu = 0.968123 (sec), leaf count = 23 \[ \text {DSolve}\left [a+y''(x)-2 y(x)^3-x y(x)=0,y(x),x\right ] \]
Maple: cpu = 0.187 (sec), leaf count = 0 \[ \text {could not solve} \]