function to count in the cell a1=a1+a2

[oleana]

I need to create user function to count in the cell fro example a1 summ
of this cell and another one (a1=a1+a2 or like a1=summ(a1;a2)).

if i'll use itaration - it will recalculate cell value after savings or
other calculations

 

[Guest]

I don't really understand what you are trying to do.

My understanding is:

A1: 2
A2: 3
A1: should show 5?

It is really impossible to do this and I would encourage you to try another
method.