On Sep 12, 9:06 pm, I wrote:
So the formula for A35 should be the array formula (commit with
ctrl-shift-Enter):
=sqrt( ( s - sqrt( sum( (A1:A34-m)^2 )/n ) )^2 *n/2 ) + m

Hmm, I don't think so. Obviously s^2 - v does not equal (s -
sqrt(v))^2.

Oh well, back to the drawing board. As I noted previously, I believe
the (original) formula is mathematically correct. But I need to deal
with the numerical error caused by binary computer arithmetic. Sorry,
don't have the time for this now. Perhaps someone else can offer a
solution.