## November 23, 2009

### The Curious Incident of the Dog

In Sir Arthur Conan Doyle’s Sherlock Holmes story ‘Silver Blaze’, we find:

‘Is there any other point to which you would wish to draw my attention?’

‘To the curious incident of the dog in the night-time.’

‘The dog did nothing in the night-time.’

‘That was the curious incident,’ remarked Sherlock Holmes.

Here is a sequence: 1, 2, 4, 7, 8, 11, 14, 16, 17, 19, 22, 26, 28, 29, 41, 44

Having taken Holmes’s point on board: what is the next number in the sequence?

### 3 comments by 2 or more people

1. #### Simon Whitehouse

This has got me a bit stumped. But.

In Mark Haddon’s, The Curious Incident Of The Dog In The Night-time, there is a lovely description of prime numbers:

“Prime numbers are what is left when you have taken all the patterns away. I think prime numbers are like life. They are very logical but you could never work out the rules, even if you spent all your time thinking about them.”

Which lead me to noting the numbers that aren’t in the sequence listed. I came up with the following

0, 3, 5, 6, 9, 10, 12, 13, 15, 18, 20, 21, 23, 24, 25, 27, 30, 31, 32, 33,
34, 35, 36, 37, 38, 39, 40, 42

From which the 3s and 5s jumped out at me. There are certainly no multiples of either in the sequence in the question. That still leaves me with

13, 23, 31, 32, 34, 37, 38

so I’m guessing that the sequence in the question also has any number with the digit 3 or 5 in it stripped out as well. By which logic, the next numbers in the sequence will be

46, 47, 49, 61, 62, 64, 67 . . . . .

I’m not convinced that it’s the right answer though

23 Nov 2009, 11:00

2. #### Samuel Boulby

I’m with you on that Simon – no multiples of 3 and 5, no numbers containing the digits 3 and 5, that’s the pattern.

23 Nov 2009, 11:09

3. #### Eleanor Lovell

25 Nov 2009, 14:26

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