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Birthday puzzle

28 May 2008 19:38

Today is my birthday. I am now N years old. You can work out N from the following:

  • N is a prime number;
  • The last time my age was a prime was six years ago (i.e N-6 is prime and no other numbers between N-6 and N are prime);
  • N is not a member of any twin-prime pairing: see the definition of a twin prime if needed;
  • You can assume that N is less than 50 :-D

There is only one unique solution to the above.

And Happy 40th Birthday to Kylie, too.

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8 Responses to “Birthday puzzle”

  1. mattj says:
    28 May 2008 at 20:03

    37?

  2. Geoff Hogg says:
    28 May 2008 at 20:33

    Aren’t you just the same age as me now?

  3. Simon Ward says:
    28 May 2008 at 21:24

    Unsolvable! age[davee] is surely defined to be >50? :P

    I think you’re about a year younger than my mum.

  4. davee says:
    28 May 2008 at 22:07

    /me boots sward into orbit…

  5. davee says:
    28 May 2008 at 22:07

    mattj: Yep, that’s right :-)

  6. Simon Ward says:
    28 May 2008 at 22:55

    Oops, I was out. Make that 11 years younger. :) I had 47, with 41 being the previous prime, which is just not true (43). :(

  7. mrben says:
    29 May 2008 at 06:56

    I got it right \o/

  8. martin says:
    29 May 2008 at 17:50

    young wipper-snapper, happy birthday for yesterday anyways.