Formula to calculate next number in sequence based on varying criteria

Evening all

An artist friend has asked me to put together a sheet for her to keep track of limited edition prints that she produces. She has say 15 paintings and each painting could have 50 numbered prints that she sells, because she has them printed as and when they sell, she needs to be able to keep track of the next number in the sequence to ensure she doesn't sell print number 37 of 50 twice for example.

She'd like a table where she can enter the name of the painting and the sheet will tell her the next sequential number based on previous sales

I may be overthinking but I can't quite get my head round it, any help would be greatly appreciated

Attached is a very basic table to give you an idea Next number in sequence .xlsx

Many thanks in advance for any thoughts and assistance

Greg

Hi Richard

Thanks for your reply, I'd thought about doing a COUNTIFS formula however I've found a slight problem with it.

If you enter print numbers 1 through to 5, the formula shows 6 as being the next print edition in sequence which would be correct, however if I make a mistake and enter print number 7 in column C rather than 6 as the formula suggested, my next number in sequence according to the formula is print number 7 however that's already been used.

In this instance I would need it to recognise the gap in the sequence and return print number 6 as being the next in sequence, and then calculate that 8 would be next (as I'd already used 7 when making the error)

Does that make sense?

Many thanks

Greg