\[ a y(x)+(b+x) y'(x)+x y''(x)=0 \] ✓ Mathematica : cpu = 0.0206616 (sec), leaf count = 40
DSolve[a*y[x] + (b + x)*Derivative[1][y][x] + x*Derivative[2][y][x] == 0,y[x],x]
\[\left \{\left \{y(x)\to c_1 e^{-x} U(b-a,b,x)+c_2 e^{-x} L_{a-b}^{b-1}(x)\right \}\right \}\] ✓ Maple : cpu = 0.073 (sec), leaf count = 30
dsolve(x*diff(diff(y(x),x),x)+(x+b)*diff(y(x),x)+a*y(x)=0,y(x))
\[y \left (x \right ) = {\mathrm e}^{-x} \left (\KummerU \left (-a +b , b , x\right ) c_{2}+\KummerM \left (-a +b , b , x\right ) c_{1}\right )\]