Hi⁡(z)=ⅇ±2⁢π⁢ⅈ/3⁢Hi⁡(z⁢ⅇ±2⁢π⁢ⅈ/3)+2⁢ⅇ∓π⁢ⅈ/6⁢Ai⁡(z⁢ⅇ∓2⁢π⁢ⅈ/3).