WP 34S mini-challenge

[Sanjeev Visvanatha]

(01-21-2014 11:48 AM)Paul Dale Wrote:  ...
Even using the statistical Σ+ command doesn't seem to help.
...

It works using Σ+ so long as the summation registers are clear:

LBL D
Σ+
X<>L
X^2
Σ+
x̄
RTN

I believe the stack remains 'unchanged'. However, the Y register is altered (I believe) through the use of the mean command. In this case though, original Y is returned back to Y. Due to the requirement that the summation registers are cleared prior to execution, the criteria of the challenge were not met.