/sci/ - Science & Math

Hello /sci/

A very quick question. Is there such a symbol as "cannot be equal to"? I know obviously that there is a "is not equal to" and an "approximately equal to" but I was wondering, in terms of logic, if there was a cannot be equal to?

Something like:

If a = 1 and b = 2 and c = 3 then d <cannot be equal to> 4?

Thanks for your help.

>Pic unrelated. I just needed a pic.

mind reading