Question 1118560
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I have no idea how the other tutor came up with a formula for the n-th term in your sequence....<br>
However, in fact this is an invalid question, because you could put ANY number next and it would be a valid sequence.<br>
The fact that there is a simple formula that produces the first four terms of the sequence makes his answer of 15961 a PROBABLE answer to the question; but it can't be said that it is THE answer.<br>
For ANY question like this, where you are only given some numbers in a sequence, without any information on what kind of sequence it is, it is IMPOSSIBLE to know the "RIGHT" answer.