Pn(α,β)⁡(x)=∑ℓ=0n(n+α+β+1)ℓ⁢(α+ℓ+1)n-ℓℓ!⁢(n-ℓ)!⁢(x-12)ℓ=(α+1)nn!⁢F12⁡(-n,n+α+β+1α+1;1-x2),