Conversion from special function to continued fraction

 

Bessel function of the first kind of order n is expressed as

 

 

in infinite products. Here,  are positive roots of Jn(x)=0.

 

We can use the following formula

 

     (regular expression)

   in special form

 

as in 0220 but it is difficult to find the roots or it take a while to find out the roots.

 

Another way is expand

 

 

in series. We can use the following formula

 

  (regular expression)

   in special form

 

 

Hypergeometric function is defined and expanded as

 

 

We can use the following formula

 

   (regular expression)

   in special form of 0218.

 

Regarding

 

 

we get

 

 

in special form of continued fraction

 

When x=1, in particular,

 

                when c>0, c-a-b>0, c>a, and c>b.