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## #1 2013-03-09 11:55:17

infinitebrain
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### Sequence question

Given the sequence

find k
I found the answer as 291, through a tedious guess and check method, but I'd like someone to explain in simpler terms how to find k.

Last edited by infinitebrain (2013-03-09 11:55:30)

The best thing about life is you don't know what to expect

## #2 2013-03-09 12:16:56

bobbym

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### Re: Sequence question

Hi;

You can use differences to get the answer

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #3 2013-03-09 14:23:30

Stormtangent
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### Re: Sequence question

Hi,

If you subtract consecutive terms, you see that you get:

Subtracting again, you get

You could find the quadratic.  However, another way is to realize that
, which, after solving, gives

Last edited by Stormtangent (2013-03-09 14:25:26)

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