\[ y^{(4)}(x)=0 \] ✓ Mathematica : cpu = 0.0032823 (sec), leaf count = 24
\[\left \{\left \{y(x)\to c_4 x^3+c_3 x^2+c_2 x+c_1\right \}\right \}\] ✓ Maple : cpu = 0.013 (sec), leaf count = 21
\[y \relax (x ) = \frac {1}{6} x^{3} c_{1}+\frac {1}{2} x^{2} c_{2}+c_{3} x +c_{4}\]