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Introducing the associated Bessel polynomials in terms of two non-negative integers, and under an integrability condition we simultaneously
factorize their corresponding differential equation into a product of the ladder operators by four different ways as shape invariance symmetry
equations. This procedure gives four different pairs of recursion relations on the associated Bessel polynomials. In spite of description of Bessel
and Laguerre polynomials in terms of each other, we show that the associated Bessel differential equation is factorized in four different ways
whereas for Laguerre one we have three different ways.
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