\[ (a+b+x) y'(x)+a y(x)+x y''(x)=0 \] ✓ Mathematica : cpu = 0.0243341 (sec), leaf count = 37
DSolve[a*y[x] + (a + b + x)*Derivative[1][y][x] + x*Derivative[2][y][x] == 0,y[x],x]
\[\left \{\left \{y(x)\to c_1 e^{-x} U(b,a+b,x)+c_2 e^{-x} L_{-b}^{a+b-1}(x)\right \}\right \}\] ✓ Maple : cpu = 0.073 (sec), leaf count = 26
dsolve(x*diff(diff(y(x),x),x)+(x+a+b)*diff(y(x),x)+a*y(x)=0,y(x))
\[y \left (x \right ) = {\mathrm e}^{-x} \left (\KummerU \left (b , a +b , x\right ) c_{2}+\KummerM \left (b , a +b , x\right ) c_{1}\right )\]