When searching a plain number, sometimes the calculator widget triggers even though the inputted search is not a calculation (e.g. containing + - / *). I came across this when attempting to search a specific product code for a product which didn't have much of a web presence.
It seems that this issue generally only arises when there are no actual search results. So when results appear, the calculator does not appear. The one anomaly for this is the below search (which, when repeated today, does not reveal any web results — see here).
Some examples of the calculator triggering:
Some examples of the calculator not triggering:
