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
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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
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That can also be expressed as
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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
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