This is a follow-up of this question/answer.
I'm working on a recursive integral more complicated than the one on the linked question, but this one can be used as an example.
I would like to obtain a closed expression for the dependence of the integral on the dimension $d$, that is, on the recursive parameter. In other words, I want to know what the general term of the recurrence relation is.
RSolve is not able to find it (in my example).