.. I'm confused with your INT though?!?!

I used: ... INT((ROWS($A$1:A1)-1)/3) ..
as it produces a triplet series of zero's, 1's, 2's .. when copied down
which nicely syncs and increments the row for both:
'ED Numbers'!B1 & 'ED Numbers'!C1
in every 4th line when the formula in the starting cell is copied down

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Rgds
Max
xl 97
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Singapore, GMT+8
xdemechanik
http://savefile.com/projects/236895
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