Mathematicians have long worked on the problem of expressing all numbers up to 100 as the sum of three cubes. The solution for the last remaining number – 42 – has finally been found.

Now 42, as everyone knows, is the answer to the Ultimate Question of Life, the Universe, and Everything in Douglas Adams’s beloved series The Hitchhiker’s Guide to the Galaxy, given by the computer named Deep Thought. And while the real-life problem of 42 was a different one, it certainly needed tremendous computing power to be solved.

The search to express all numbers up to 100 as the sum of three cubes started way back in 1954. The last remaining number was 42, the solution to which has been found 65 years later. This last solution involves cubes of 17-digit numbers.

“The most interesting aspects this time around were sociological rather than mathematical,” mathematician Andrew Booker said, highlighting the involvement of volunteer computing organisation Charity Engine in the process.

The next number that the researchers are interested in is 3. “The reason why it often gets ignored is that there are a couple of small solutions,” Booker explained.