Ten is non-controversial ... If he had chosen 41 or 43, the gag falls flat. They are both odd and prime numbers, and they feel elusive. It's not funny to say that the meaning of life is mysterious.

A Sierpinski number is an odd number – call it k – for which the expression k × 2 n + 1 is not prime. This has to hold for any positive, whole value of n. These numbers are few and far betwee ...

Humans are so smart that we can easily learn the difference between even numbers and odd numbers. And until a new study emerged, humans believed we were the only species capable of this feat ...