✓ Mathematica : cpu = 0.0131594 (sec), leaf count = 29
DSolve[2*Derivative[2][y][x] + 4*x*Derivative[3][y][x] + x^2*Derivative[4][y][x] == 0,y[x],x]
✓ Maple : cpu = 0.011 (sec), leaf count = 17
dsolve(x^2*diff(diff(diff(diff(y(x),x),x),x),x)+4*x*diff(diff(diff(y(x),x),x),x)+2*diff(diff(y(x),x),x)=0,y(x))