\[ \int \frac {\text {Si}(b x)}{x^3} \, dx \]
Optimal antiderivative \[ -\frac {b \cos \left (b x \right )}{4 x}-\frac {b^{2} \sinIntegral \left (b x \right )}{4}-\frac {\sinIntegral \left (b x \right )}{2 x^{2}}-\frac {\sin \left (b x \right )}{4 x^{2}} \]
command
integrate(sin_integral(b*x)/x^3,x, algorithm="maxima")
Maxima 5.46 SBCL 2.0.1.debian via sagemath 9.6 output
\[ -\frac {1}{4} \, b^{2} {\left (-i \, \Gamma \left (-2, i \, b x\right ) + i \, \Gamma \left (-2, -i \, b x\right )\right )} - \frac {\operatorname {Si}\left (b x\right )}{2 \, x^{2}} \]
Maxima 5.44 via sagemath 9.3 output
\[ \int \frac {{\rm Si}\left (b x\right )}{x^{3}}\,{d x} \]________________________________________________________________________________________