Approximate Closed-Form Formulas for the Zeros of the Bessel Polynomials

Figure 1

Real and imaginary parts of the zeros of the normalized Bessel polynomials 𝑦_𝑛(2𝑧/(2𝑛+𝑎−2);𝑎) for 𝑎=2,40,100. They are plotted as functions of 𝑘 for 𝑛=100,200,300,400,500, in gray-level intensity, from lower to higher, according to the value of 𝑛.

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