It’s so nice to see mathematics playing an important part in popular television. In tonight’s Dr Who the spaceship crew had to find the next number in the sequence 313, 331, 367, …. Dr Who recognises this as a sequence of happy primesÂ with the next one being 379. It’s all explained at that Wikipedia articleÂ and a longer version of the sequence can be found at the wonderful The On-Line Encyclopedia of Integer Sequences.
It’s interesting that the Dr Who reference was put in the Wikipedia article half-an-hour before the programme was aired so probably an inside job. I was delighted thatÂ in the programme Dr WhoÂ asked if mathematics was so dumbed down that recreational maths wasn’t studied any more. As Russell T.Â Davies, the head writer,Â said in tonight’sÂ Dr Who Confidential, the programme reflects current concerns, so this problem has clearly reached a wider audience than I imagined was the case.