[aboeing]

Hi, I would like to create my own "large operator" (like a 'sum'), but I am
not sure how I can do this.
I have tried making a 1x3 matrix however this makes the central part too
small and is then inconsistant with the rest of the equations formatting. If
I just try using a 'script' then I can not get the upper and lower boxes to
sit directly above & below the symbol.

The operator I am trying to create is a "for each" operator (an upside down
A), starting from i=0 and going to n.

Any advice would be appreciated.
Thanks.