Gauss's continued fraction

 

Some manipulations of exponential

 

For

   as in 0327

 

when a=1 and b=1, it is known that

 

    in special form

 

The other way is start from the resulting formula

 

 

as in 0401. That is,

 

     in special form

 

 

We can express error function and Gaussian cdf in terms of 1F1(a,b;x).

 

Error function is defined as

 

 

That can also be expressed as

 

or

   in special form

 

from the formula

 

 as in 0401

 

and after shifting the negative signs from up to front by the rule of signs.

 

We can also express Gaussian cdf function as

 

 

because