Enter the following array formula to cell A2:
=IF(TRUE,IF(MAX(ROW($1:1)*ISNUMBER(A$1:A1))=0,1,2) ,3)
Use Ctrl-Shift-Enter to enter since it's an array formula.

It runs without any issues but when you try Tools-Formula
Auditing-Evaluate Formula, Excel 2003 crashed on the first step, which is to
evaluate ROW($1:1).

If you enter the formula as a regular one, no crash when evaluating.

If I remove the outer IF, no crash when evaluating.

I haven't tried it on other versions of Excel. I am just wondering if this
is a bug and the problem can be reproduced.

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