Pl note that the correct final result is read-off in H8 only when all 11
source cells are completely filled with numbers (or letter "R") or when they
are completely cleared.

This is consistent with your original post's intents as expressed eg:
AND(Y8,AA8,AB8,AC8,AL8 ... =49)

Ignore H8's intermediate returns as the 11 source cells are progressively
filled. Read off the H8 result only when the source is completely filled /
cleared.
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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