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A175838
Let rho(n) be the first positive root of Bessel function J_n(x). This sequence is decimal expansion of derivative rho'(0)=1.54288974...
0
1, 5, 4, 2, 8, 8, 9, 7, 4, 2, 5, 9, 9, 3, 1, 3, 6, 8, 8, 0, 7, 0, 3, 2, 1, 4, 2, 1, 4, 7, 1, 4, 3, 5, 5, 6, 1, 6, 9, 8, 4, 6, 0, 7, 8, 7, 3, 5, 0, 1, 9, 7, 5, 8, 9, 3, 5, 2, 5, 2, 9, 4, 4, 1, 0, 2, 6, 8, 2, 5, 6, 4, 6, 9, 7, 2, 9, 1, 1, 2, 6, 0, 5, 0, 2, 3, 8, 2, 7, 4, 6, 7, 3, 8, 1, 0, 4, 7, 5, 6, 6, 1, 5, 4, 6
OFFSET
1,2
MAPLE
From R. J. Mathar, Sep 22 2010: (Start)
Digits := 120 : Jnudnu := proc(nu, z, kmax) -add( (-1)^k*Psi(nu+k+1)/GAMMA(nu+k+1)*(z/2)^(2*k+nu)/k! , k=0..kmax) ; evalf(%) ; end proc:
Jprime := diff(BesselJ(0, x), x) ; z := evalf(BesselJZeros(0, 1)) ; denomin := subs(x=z, Jprime) ;
for kmax from 30 to 70 by 10 do numerat := Jnudnu(0, z, kmax) ; c := evalf(-numerat/denomin) ; print(c) ; end do: # Abramowitz-Stegun 9.1.64
(End)
MATHEMATICA
N[(Pi BesselY[0, BesselJZero[0, 1]])/(2 BesselJ[1, BesselJZero[0, 1]]), 200]
PROG
(PARI) besseljzero'(0) \\ Charles R Greathouse IV, Oct 23 2023
CROSSREFS
Cf. A115368. - R. J. Mathar, Sep 22 2010
Sequence in context: A257972 A222307 A368274 * A347272 A097960 A019712
KEYWORD
cons,nonn
AUTHOR
STATUS
approved