\[ (a+x) y(x)+x y''(x)+y'(x)=0 \] ✓ Mathematica : cpu = 0.0121195 (sec), leaf count = 61
\[\left \{\left \{y(x)\to c_1 e^{-i x} U\left (\frac {1}{2} i (a-i),1,2 i x\right )+c_2 e^{-i x} L_{-\frac {1}{2} i (a-i)}(2 i x)\right \}\right \}\] ✓ Maple : cpu = 0.148 (sec), leaf count = 39
\[\left \{y \left (x \right ) = \left (c_{1} \KummerM \left (\frac {i a}{2}+\frac {1}{2}, 1, 2 i x \right )+c_{2} \KummerU \left (\frac {i a}{2}+\frac {1}{2}, 1, 2 i x \right )\right ) {\mathrm e}^{-i x}\right \}\]