\[ \boxed { a{\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) - \left ( ab+c+x \right ) {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) + \left ( b \left ( x+c \right ) +d \right ) y \left ( x \right ) =0} \]
Mathematica: cpu = 0.045006 (sec), leaf count = 99 \[ \left \{\left \{y(x)\to c_1 e^{b x} H_d\left (\frac {x}{\sqrt {2} \sqrt {a}}-\frac {a b-c}{\sqrt {2} \sqrt {a}}\right )+c_2 e^{b x} \, _1F_1\left (-\frac {d}{2};\frac {1}{2};\left (\frac {x}{\sqrt {2} \sqrt {a}}-\frac {a b-c}{\sqrt {2} \sqrt {a}}\right )^2\right )\right \}\right \} \]
Maple: cpu = 0.047 (sec), leaf count = 61 \[ \left \{ y \left ( x \right ) ={\it \_C1}\,{{\rm e}^{bx}}{{\sl M}\left (- {\frac {d}{2}},\,{\frac {1}{2}},\,{\frac { \left ( ab-c-x \right ) ^{2} }{2\,a}}\right )}+{\it \_C2}\,{{\rm e}^{bx}}{{\sl U}\left (-{\frac {d}{2 }},\,{\frac {1}{2}},\,{\frac { \left ( ab-c-x \right ) ^{2}}{2\,a}} \right )} \right \} \]