Gauss's continued fraction

 

Suppose that we can say

 

     for i=1,2,3,4,c

 

where fi is a function and ki is a constant and x is a variable that is used in function fi.

 

 

  or

 

This can be recursively expanded as

 

 or  for i=1

 

We have the following identity

 

 

where we can regard

 

 and

 

That is, we can expand it as

 

or

  in special form

 

Applying gamma-shaped multipliers repeatedly, we get

 

or

   in special form

 

Thus

 

   in special form