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# Non Linear Recurrence Relation watch

1. Can we solve

?
2. (Original post by meef cheese)
Can we solve

?
Are you looking for the closed form of this recurrence relation?

Simply write down the first few terms and look for the pattern.

You should now be able to write down the closed form.

Hint: Express the denominator as a power of 2.

Spoiler:
Show
Unparseable or potentially dangerous latex formula. Error 4: no dvi output from LaTeX. It is likely that your formula contains syntax errors or worse.
u_{n}={(-2)^{(1-2^n)} a^{(2^n)}
3. (Original post by Mr M)
Are you looking for the closed form of this recurrence relation?

Simply write down the first few terms and look for the pattern.

You should now be able to write down the closed form.

Spoiler:
Show
Your terms are incorrect from u_2 onwards.
4. (Original post by yusufu)
Your terms are incorrect from u_2 onwards.
Oops so they are.

I will fix it. Sorry about that.

OP, please ignore the post immediately above. The second post in this thread is OK now.
5. (Original post by Mr M)
Oops so they are.

I will fix it. Sorry about that.

OP, please ignore the post immediately above. The second post in this thread is OK now.
lol. It's still incorrect! Every term except for u_0 is going to be negative.
6. (Original post by yusufu)
lol. It's still incorrect! Every term except for u_0 is going to be negative.
I want to cry. How's it looking now? You would think I would have taken more care after you picked up my first mistake.

Anyway OP there was nothing wrong with my advice. All that was lacking was an ability to square and divide by -2.

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Updated: November 9, 2008
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