Would someone tell me the exact mathematical equation for NORMDIST
(x,mean,standard_dev,TRUE)?

I have found an equation in Excel Help which is for cumulative = FALSE and
written that the formula should integrate from negative infinity to x for
TRUE.

There are some equations for such integration in mathworld.wolfram.com with
error function (erf) but it does not give the same result as does the Excel
give.

For example, NORMDIST(0.3,4,1.5,TRUE) = 0.006819 (from Excel) and now I
wanted to know the equation which gave that value (0.006819). Any help in
this regard would be highly appreciated.