## Three Two Three Sequence

What number belongs at the beginning of this sequence?

?, 3, 2, 3, 9, 2, 4, 8, 4, 3, 7, 6

3 ½.

If you break up the numbers into groups of 4, a,b,c,d, then 2 × |a – d| = |b – c|.

9 2 4 8 → 2 × |9 – 8| = |2 – 4|, or 2 × 1 = 2

4 3 7 6 → 2 × |4 – 6| = |3 – 7|, or 2 × 2 = 4, so

n 3 2 3 → 2 × |3 ½ – 3| = |3 – 2|, or 2 × ½ = 1;

I’m not sure this is the correct solution, but it’s the best I’ve found so far. Email me if you know of a better one.

Posted in Brain Teasers

1 Comment on "Three Two Three Sequence"Nick Mitchell says

July 17, 2014 @ 12:26

My guess is that the numbers are the lengths of the words in an earlier version of this riddle, but the words have unwittingly been changed.

The words “At the beginning of this sequence” have 2,3,9,2,4,8 letters in that order, which makes up part of the sequence.

So the original riddle could have been something like “To put at the beginning of this sequence, find the missing number.”

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