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14 Legendre and Related FunctionsReal Arguments

§14.11 Derivatives with Respect to Degree or Order

14.11.2 ∂∂ν⁡𝖰νμ⁡(x)=−12⁢π2⁢𝖯νμ⁡(x)+π⁢sin⁡(μ⁢π)sin⁡(ν⁢π)⁢sin⁡((ν+μ)⁢π)⁢𝖰νμ⁡(x)−12⁢cot⁡((ν+μ)⁢π)⁢𝖠νμ⁡(x)+12⁢csc⁡((ν+μ)⁢π)⁢𝖠νμ⁡(−x),

where

14.11.3 𝖠νμ⁡(x)=sin⁡(ν⁢π)⁢(1+x1−x)μ/2⁢∑k=0∞(12−12⁢x)k⁢Γ⁡(k−ν)⁢Γ⁡(k+ν+1)k!⁢Γ⁡(k−μ+1)⁢(ψ⁡(k+ν+1)−ψ⁡(k−ν)).

(14.11.1) holds if 𝖯νμ⁡(x) is replaced by Pνμ⁡(x), provided that the factor ((1+x)/(1−x))μ/2 in (14.11.3) is replaced by ((x+1)/(x−1))μ/2. (14.11.4) holds if 𝖯νμ⁡(x), 𝖯ν⁡(x), and 𝖰ν⁡(x) are replaced by Pνμ⁡(x), Pν⁡(x), and Qν⁡(x), respectively.

See also Szmytkowski (2006, 2009, 2011, 2012), Cohl (2010, 2011) and Magnus et al. (1966, pp. 177–178).