rsolve problems other than in documentation not getting executed.

Questions
,
1

can anyone help?

2

Attach an example notebook showing ones that do and ones that do not?

3

sir,here is an attached notebook

4

sir, please find the attached notebook

5

Your example:

In[1]:= RSolve[{(2 n + 1) a[n] == a'[n + 1] - a'[n - 1]}, a[n], n]

RSolve::deqx: Supplied equations are not difference equations of the given functions.

a’ is usually used for the derivative of a continuous function a.

Dropping the derivative mark gives,

In[1]:= RSolve[{(2 n + 1) a[n] == a[n + 1] - a[n - 1]}, a[n], n]

Out[1]= 
{{a[n] -> BesselI[1/2 + n, -1]*C[1] + BesselK[1/2 + n, 1]*C[2]}}

where C[1] and C[2] depend on the initial conditions.

6

Thank you sir.