The formula:
For all x from 1 to 10, if (Sell <= Buy * x) then x, else ">=10"
I thought I might be able to cheat a little with the sequence function:
=ARRAYFORMULA(MIN(IF(Sell range <= SEQUENCE(4,1,1) * Buy, SEQUENCE(4,1,1))))
But since the sell range is in the min function, I only get the first result.
Is there a good way to make this formula expandable? It's not necessary, I'm just really curious.