Welcome to the forum. To get Fn you must be able to solve the recurrence for the Fibonacci sequence. You can use the characteristic polynomial to do that.

]]>Welcome to the forum.

You should find all you need here:

http://www.maths.surrey.ac.uk/hosted-si … ibrab.html

There are also some good poages on the MIF site:

http://www.mathsisfun.com/numbers/fibon … uence.html

Bob

]]>Hence, the Fibonacci sequence 1, 1, 2, 3, 5, 8, 13, 21,...

Question: How many pairs of rabbits will there be after n months?

Explain why the answer is F(subn).

Any help would be much appreciated.

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