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16 Generalized Hypergeometric Functions & Meijer G-FunctionGeneralized Hypergeometric Functions

§16.3 Derivatives and Contiguous Functions

Contents
  1. §16.3(i) Differentiation Formulas
  2. §16.3(ii) Contiguous Functions

§16.3(i) Differentiation Formulas

16.3.1 dndznFqp(a1,,apb1,,bq;z)=(𝐚)n(𝐛)nFqp(a1+n,,ap+nb1+n,,bq+n;z),
16.3.2 dndzn(zγFqp(a1,,apb1,,bq;z))=(γn+1)nzγnFq+1p+1(γ+1,a1,,apγ+1n,b1,,bq;z),
16.3.3 (zddzz)n(zγ1Fqp+1(γ,a1,,apb1,,bq;z))=(γ)nzγ+n1Fqp+1(γ+n,a1,,apb1,,bq;z),
16.3.4 dndzn(zγ1Fq+1p(a1,,apγ,b1,,bq;z))=(γn)nzγn1Fq+1p(a1,,apγn,b1,,bq;z).

Other versions of these identities can be constructed with the aid of the operator identity

16.3.5 (zddzz)n=zndndznzn,
n=1,2,.

§16.3(ii) Contiguous Functions

Two generalized hypergeometric functions Fqp(𝐚;𝐛;z) are (generalized) contiguous if they have the same pair of values of p and q, and corresponding parameters differ by integers. If pq+1, then any q+2 distinct contiguous functions are linearly related. Examples are provided by the following recurrence relations:

16.3.6 zF10(;b+1;z)+b(b1)F10(;b;z)b(b1)F10(;b1;z)=0,
16.3.7 F23(a1+2,a2,a3b1,b2;z)a1(a1+1)(1z)+F23(a1+1,a2,a3b1,b2;z)a1(b1+b23a12+z(2a1a2a3+1))+F23(a1,a2,a3b1,b2;z)((2a1b1)(2a1b2)+a1a12z(a1a2)(a1a3))F23(a11,a2,a3b1,b2;z)(a1b1)(a1b2)=0.

For further examples see §§13.3(i), 15.5(ii), and the following references: Rainville (1960, §48), Wimp (1968), and Luke (1975, §5.13).