\[\operatorname{Bi}\left(x\right)=\frac{1}{\pi}\int_{0}^{\infty}\exp\left(-{%
\tfrac{1}{3}}t^{3}+xt\right)\,\mathrm{d}t+\frac{1}{\pi}\int_{0}^{\infty}\sin%
\left(\tfrac{1}{3}t^{3}+xt\right)\,\mathrm{d}t.\]