Question 1152504
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As tutor @ikleyn says in her response, it is impossible to find THE answer to any problem like this, because ANY next number makes a valid sequence.<br>
So any time spent trying to find an answer is ultimately a waste of time, because it is impossible to know what the "right" answer is.<br>
Spend a few moments, if you want to, looking for some simple pattern; but any more than that is pointless.<br>
In this case, if you split the given sequence into two intertwined sequences, you can see what a POSSIBLE answer is:<br><pre>
  2   4   8   ?
    3   7   11   ?</pre>