I'm trying to calculating the four point function for the 3D Ising model. To do so I need to calculate the 3D Conformal Blocks . I found a paper which has a recursive relation for calculating the Conformal Blocks https://link.springer.com/content/pdf/10.1007%2FJHEP06%282014%29091.pdf equation (3.10) but I am unsure how to actually implement it. I want to compute 3.10 up to r^12. I imagine my expression is going to look like a sum of the h^infinity times coefficients with powers of r. However I'm not so sure that is the correct interpretation of this recursion relation. If anyone can point me in the right direction that would be much appreciated.Also I do not know how many times I need to plug the right hand side into the left hand side. If I want to order 12 I imagine I do it 12 times.

The authors are Filip Kos,a David Polanda and David Simmons-Duffinb

and the title is Bootstrapping the O(N) vector models of the referenced paper.