Google is trying fix a mysterious bug that returns pages and pages of almost exclusively pornographic and adult results when users enter certain equations or search strings.
A Google search for "-4(1/4)" at the time of writing revealed the result on a calculator, below which were several pages of porn links with titles such as "four guys and a hooker" and others too lewd to repeat here.

According to the Age, other search strings that return mostly adult links included, "1 2"-1, "1 2" -2, "h 3" -h, "1 4" -4 and "apple 1" - apple.

The first person to notice the bug appears to be a poster on Quora who wondered what was causing this 'equation porn' when users search for contradictory queries.

Google search engineer Jeremy Hoffman said that firm was working on a " bug fix".