Yl,m⁡(12⁢π,ϕ)={(-1)(l+m)/2⁢ⅇⅈ⁢m⁢ϕ2l⁢(12⁢l-12⁢m)!⁢(12⁢l+12⁢m)!⁢((l-m)!⁢(l+m)!⁢(2⁢l+1)4⁢π)1/2,12⁢l+12⁢m∈ℤ,0,12⁢l+12⁢m∉ℤ.