If it would be like 1,3,7,9,13,14,15,16,18,20 then you can create a list of
numbers 1 to 20 (assume they are in A1:A20), then adjacent to that list use
a formula like

=IF(ISNUMBER(MATCH(A1,MySequence,0)),"",A1)

where MySequence is the list you want to check, copy down to B20

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Regards,

Peo Sjoblom

(No private emails please)


"Nash" wrote in message
...
Looking for a function or formula that will identify a missing number in a
range of cells containing a sequence of numbers.

Can anyone help?