There is a logical pattern to the following series of numbers. What are the next three numbers in the series?

15 21 25 27 33 35 39 ...

I perceive a 'refletive' pattern in the intervals between the numerals.

That pattern is: [2] 6 4 2 6 2 4 6 2 4 ...
making the series:[13]15 21 25 27 33 35 39 45 47 51 ...

Well! It's logical, but does it match the logic of Gautam?
Number Series may need some guiding rules.

123.. maybe the start of 1234.. or 1235.. or 1236..

I an examination situation (eg IQ), if my set of rules work then why should I be penalised?

Posted by Brian Nowell on 2003-02-11 19:23:17