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#1 2013-03-09 11:55:17
- infinitebrain
- Full Member
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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
- Administrator
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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.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
#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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