10 Bessel FunctionsSpherical Bessel Functions

§10.51 Recurrence Relations and Derivatives

Contents
  1. §10.51(i) Unmodified Functions
  2. §10.51(ii) Modified Functions

§10.51(i) Unmodified Functions

Let fn⁡(z) denote any of 𝗃n⁡(z), 𝗒n⁡(z), 𝗁n(1)⁡(z), or 𝗁n(2)⁡(z). Then

10.51.1 fn−1⁡(z)+fn+1⁡(z) =((2⁢n+1)/z)⁢fn⁡(z),
n⁢fn−1⁡(z)−(n+1)⁢fn+1⁡(z) =(2⁢n+1)⁢fn′⁡(z),
n=1,2,…,
10.51.2 fn′⁡(z) =fn−1⁡(z)−((n+1)/z)⁢fn⁡(z),
n=1,2,…,
fn′⁡(z) =−fn+1⁡(z)+(n/z)⁢fn⁡(z),
n=0,1,….
10.51.3 (1z⁢ddz)m⁡(zn+1⁢fn⁡(z)) =zn−m+1⁢fn−m⁡(z),
m=0,1,…,n,
(1z⁢ddz)m⁡(z−n⁢fn⁡(z)) =(−1)m⁢z−n−m⁢fn+m⁡(z),
m=0,1,….

§10.51(ii) Modified Functions

Let gn⁡(z) denote 𝗂n(1)⁡(z), 𝗂n(2)⁡(z), or (−1)n 𝗄n⁡(z). Then

10.51.4 gn−1⁡(z)−gn+1⁡(z) =((2⁢n+1)/z)⁢gn⁡(z)
n⁢gn−1⁡(z)+(n+1)⁢gn+1⁡(z) =(2⁢n+1)⁢gn′⁡(z),
n=1,2,…,
10.51.5 gn′⁡(z) =gn−1⁡(z)−((n+1)/z)⁢gn⁡(z),
n=1,2,…,
gn′⁡(z) =gn+1⁡(z)+(n/z)⁢gn⁡(z),
n=0,1,….
10.51.6 (1z⁢ddz)m⁡(zn+1⁢gn⁡(z)) =zn−m+1⁢gn−m⁡(z),
m=0,1,…,n,
(1z⁢ddz)m⁡(z−n⁢gn⁡(z)) =z−n−m⁢gn+m⁡(z),
m=0,1,….