Rayleigh sums of Bessel derivatives
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Numbers
$\nu$
$n$ 
$\tau_n(\nu)$
0
1:
1/8
0
2:
1/192
0
3:
1/3072
0
4:
1/46080
0
5:
13/8847360
0
6:
11/110100480
0
7:
647/95126814720
0
8:
1133/2446118092800
0
9:
43213/1369826131968000
0
10:
777013/361634098839552000
0
11:
2540291/17358436744298496000
0
12:
31489807/3159235487462326272000
1
1:
3/8
1
2:
17/192
1
3:
79/3072
1
4:
349/46080
1
5:
19763/8847360
1
6:
652931/990904320
1
7:
3698053/19025362944
1
8:
981795931/17122826649600
1
9:
23169513667/1369826131968000
1
10:
1804374004933/361634098839552000
1
11:
25548977135149/17358436744298496000
1
12:
1371673108323559/3159235487462326272000
2
1:
1/6
2
2:
7/576
2
3:
43/34560
2
4:
439/3317760
2
5:
3947/278691840
2
6:
406067/267544166400
2
7:
522331/3210529996800
2
8:
479941/27518828544000
2
9:
1358267/726497073561600
2
10:
27397236659/136697689361350656000
2
11:
2290845843599/106624197701853511680000
2
12:
66011510671391/28660584342258223939584000
3
1:
5/48
3
2:
41/11520
3
3:
103/552960
3
4:
9631/928972800
3
5:
149/254803968
3
6:
354143/10701766656000
3
7:
962803/513684799488000
3
8:
1007992763/9492895094538240000
3
9:
391602913/65094137791119360000
3
10:
484564178227/1421655969358046822400000
3
11:
9224554117937/477676405704303732326400000
3
12:
125433050824097/114642337369032895758336000000
Definition
The Rayleigh sum $\tau_n(\nu)=\sum_{k=1}^{\infty}(j^{\prime}_{\nu,k})^{-2n}$ uses the $k$th strictly positive zero $j^{\prime}_{\nu,k}$ of the cylindrical Bessel derivative $J^{\prime}_\nu$, indexed increasingly from $k=1$ [1].
Parameters
$\nu$
—   Bessel order ($\nu\geq0$)
$n$
—   inverse-power moment order ($n\geq1$)
Formulas
(1)
For $\nu>0$, $\displaystyle \tau_1(\nu)=\frac{\nu+2}{4\nu(\nu+1)}$, $\displaystyle \tau_2(\nu)=\frac{\nu^2+8\nu+8}{16\nu^2(\nu+1)^2(\nu+2)}$ and $\displaystyle \tau_3(\nu)=\frac{\nu^3+16\nu^2+38\nu+24}{32\nu^3(\nu+1)^3(\nu+2)(\nu+3)}$ [1], equations (22), (24) and (25).
(2)
$\tau_n(0)=\sigma_n(1)$, where $\sigma_n(\nu)$ denotes the Bessel Rayleigh sum over positive zeros of $J_\nu$. In particular, $\tau_1(0)=1/8$, $\tau_2(0)=1/192$ and $\tau_3(0)=1/3072$.
(3)
For $\nu>0$, define $F_\nu(t)=\sum_{m=0}^{\infty}c_m(\nu)t^m$ with $\displaystyle c_m(\nu)=\frac{(-1)^m(\nu+2m)}{\nu\,4^m m!(\nu+1)_m}$, where $(a)_0=1$ and $(a)_m=a(a+1)\cdots(a+m-1)$. Differentiating the Bessel series [5] and normalizing its constant term to one gives $\displaystyle F_\nu(t)=\prod_{k=1}^{\infty}\left(1-\frac{t}{(j^{\prime}_{\nu,k})^2}\right)$ [4]. For $\nu=0$, use $\displaystyle c_m(0)=\frac{(-1)^m}{4^m m!(2)_m}$, from $J^{\prime}_0=-J_1$.
(4)
With $c_m(\nu)$ from (3), $\displaystyle \tau_n(\nu)=-n c_n(\nu)-\sum_{k=1}^{n-1}c_{n-k}(\nu)\tau_k(\nu)$ for $n\geq1$. Equivalently, the logarithm analytic at $t=0$ and zero there satisfies $\displaystyle \log F_\nu(t)=-\sum_{n=1}^{\infty}\frac{\tau_n(\nu)}{n}t^n$ for $|t|<(j^{\prime}_{\nu,1})^2$.
Comments
(5)
Here $J_\nu$ is the cylindrical Bessel function of the first kind. Only strictly positive roots are inverted. DLMF 10.21.1 [2] and the Bessel-extrema table count the zero at the origin as the first derivative zero when $\nu=0$; the root $j^{\prime}_{0,k}$ used here is their root with index $k+1$. For $\nu>0$, the positive-root indices agree.
(6)
For the selected integer orders $\nu=\ell$, separation into angular harmonics on the unit disk gives the radial factor $J_\ell(\sqrt{\lambda}\,r)$ [3]. The Neumann condition at $r=1$ selects $\lambda=(j^{\prime}_{\ell,k})^2$. Each radial spectrum is counted once, without angular degeneracy factors, and the constant zero mode is removed before inversion. Neumann eigenvalues of planar domains instead lists full spectra with multiplicities.
(7)
The positive roots grow linearly with their index, so the sums converge for every integer $n\geq1$ [2]. For each selected angular sector, $\tau_n(\nu)$ is the trace of the $n$th power of the inverse radial operator on its positive spectral subspace.
(8)
The identity $J^{\prime}_0=-J_1$ [2] identifies the order-zero sums with the order-one Bessel Rayleigh sums. The order-zero values are not limits of the formulas for $\nu>0$, whose first positive derivative root approaches zero as $\nu$ decreases to zero.
Programs
(P1)
Python
from fractions import Fraction as Q

def derivative_rayleigh(nu, n):
    nu = Q(nu)
    if nu < 0 or not isinstance(n, int) or n < 1:
        raise ValueError("Require rational nu >= 0 and integer n >= 1")
    order = Q(1) if nu == 0 else nu
    c, base = [Q(1)], Q(1)
    for m in range(1, n + 1):
        base = -base / (4*m*(order+m))
        c.append(base if nu == 0 else base*(nu+2*m)/nu)
    s = [Q(0)]
    for m in range(1, n + 1):
        s.append(-m*c[m] - sum(c[m-k]*s[k] for k in range(1, m)))
    return s[n]

for nu in range(4):
    for n in range(1, 13):
        print(nu, n, derivative_rayleigh(nu, n))
References
[1]
D. P. Gupta and M. E. Muldoon, Riccati equations and convolution formulae for functions of Rayleigh type, Journal of Physics A: Mathematical and General 33 (2000), 1363–1368. (arXiv) (doi)
Links
Data properties
Entries are of type: rational number
Table is complete: no (it holds every $1\leq n\leq12$ for $\nu=0,1,2,3$, the first four angular sectors of the unit disk with Neumann boundary conditions [3]; $n$ indexes inverse-operator moments, and both upper bounds are noncanonical reference prefixes chosen to cover low angular sectors and a useful span of moments with compact exact fractions)
How they were obtained:

All 48 values were computed in exact Sage rational arithmetic from the normalized Bessel series [5] and derivative product [4]. No floating-point division or truncated root sum enters the stored values.

more

An independent Python Fraction implementation using the Riccati recurrence obtained from [1], equations (19)–(21), agrees on every entry. The first three closed forms agree at each positive selected order. The order-zero values agree with the order-one Bessel Rayleigh sums. Positivity, decrease and strict log convexity were checked throughout the finite selection. Supplementary sums over 32 strictly positive derivative roots per order were computed at 70 and 100 decimal digits and compared with an explicit bound for the infinite tail. Those root checks test signs, scale and indexing conventions; they do not certify root indexing or 100 digits of an infinite sum. Known nonzero controls and deliberately perturbed values test the checkers. The attached checks are repeated on the stored entries.