\[ y(x) \left (a x+l x^2-n (n+1)\right )+x^2 y''(x)+2 x y'(x)=0 \] ✓ Mathematica : cpu = 0.023968 (sec), leaf count = 142
DSolve[(-(n*(1 + n)) + a*x + l*x^2)*y[x] + 2*x*Derivative[1][y][x] + x^2*Derivative[2][y][x] == 0,y[x],x]
\[\left \{\left \{y(x)\to c_1 e^{n \log (x)-i \sqrt {l} x} \operatorname {HypergeometricU}\left (\frac {i \left (a-2 i \sqrt {l} n-2 i \sqrt {l}\right )}{2 \sqrt {l}},2 n+2,2 i \sqrt {l} x\right )+c_2 e^{n \log (x)-i \sqrt {l} x} L_{-\frac {i \left (a-2 i \sqrt {l} n-2 i \sqrt {l}\right )}{2 \sqrt {l}}}^{2 n+1}\left (2 i \sqrt {l} x\right )\right \}\right \}\] ✓ Maple : cpu = 0.184 (sec), leaf count = 49
dsolve(x^2*diff(diff(y(x),x),x)+2*x*diff(y(x),x)+(l*x^2+a*x-n*(n+1))*y(x)=0,y(x))
\[y \left (x \right ) = \frac {c_{2} \operatorname {WhittakerW}\left (-\frac {i a}{2 \sqrt {l}}, n +\frac {1}{2}, 2 i \sqrt {l}\, x \right )+c_{1} \operatorname {WhittakerM}\left (-\frac {i a}{2 \sqrt {l}}, n +\frac {1}{2}, 2 i \sqrt {l}\, x \right )}{x}\]