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**steewan****Guest**

My teacher gave me this problem and I can't figure it out.

Jn= J(n-1) + n, j=2

I've gotten:

j1 = 1

j2 = 2 + 2

j3 = 2+3+2

j4 = 2+4+3+2

J5 = 2+5+4+3+2

Did I do this right so far and is if so, where do I go from here?

**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,797

What does j=2 mean?

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,691

Hi steewan;

Every recurrence must always have an initial condition. It appears that yours is J(0)=1. In which case J(2) is incorrect.

Also you are not computing that recurrence correctly.

where do I go from here?

Depends on what you are being asked to do. Were you asked to solve the recurrence? To plot it? To determine it's limit?

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**scientia****Member**- Registered: 2009-11-13
- Posts: 222

steewan wrote:

My teacher gave me this problem and I can't figure it out.

Jn= J(n-1) + n, j

1=2I've gotten:

j1 =2

j2 = 2 + 2

j3 = 2+3+2

j4 = 2+4+3+2

J5 = 2+5+4+3+2Did I do this right so far and is if so, where do I go from here?

It's quite obvious that . Try verifying it by mathematical induction.

*Last edited by scientia (2012-11-06 11:12:49)*

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