Kn⁡(z⁢ⅇm⁢π⁢ⅈ)=±(-1)n⁢(m-1)⁢m⁢Kn⁡(z⁢ⅇ±π⁢ⅈ)∓(-1)n⁢m⁢(m∓1)⁢Kn⁡(z).