MHB Can You Solve This Non-Constant Coefficient Difference Equation?

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The discussion centers on solving the non-constant coefficient difference equation $(x+1)y_{x+1}-(r+x)y_{x}+ry_{x-1}=0$, where r is a constant. The standard approach involves rewriting the equation to express y_{x+1} in terms of y_x and y_{x-1}, allowing for a block-wise solution. An initial value for y is necessary, typically defined over a specific range, such as 0 ≤ x ≤ 2. For instance, if y(x) is defined as x in that range, the solution for 2 ≤ x ≤ 3 can be derived as y(x) = (r+x-1)(x-1) - r(x-2)/(x). This method provides a structured way to tackle the equation based on initial conditions.
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I wish to solve a non constant coefficents difference equation $(x+1)y_{x+1}-(r+x)y_{x}+ry_{x-1}=0$ where r is a constant. Is there a characteristic equation and generic solution for this ?
 
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Actually, the standard way of solving that would be to write y_{x+1}= [(r+x)y_x- ry_{x-1}]/(x+1) and solve in "blocks". You would have to be given an "initial value" of y on, say, 0\le x\le 2. For example, if you we given that y(x)= x for 0\le x\le 2 then , for 2\le x\le 3 we would have y(x)= (r+x-1)(x-1)- r(x-2)/(x).
 

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