Bi⁡(z)=131/6⁢Γ⁡(23)⁢ⅇ-ζ⁢F11⁡(16;13;2⁢ζ)+35/622/3⁢Γ⁡(13)⁢ζ2/3⁢ⅇ-ζ⁢F11⁡(56;53;2⁢ζ),