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Conjecture re Fibonacci numbers

  1. Apr 22, 2008 #1
    Given [tex]A_1 = 3 \texttt{ and } A_n = A_{n-1}^{2} -2[/tex]; is there a way to prove the following:

    [tex]\prod_{i=1}^{n}A_{i} = F_{2^{n+1}}[/tex]

    or if someone has already proven this, can you give the reference?
  2. jcsd
  3. Apr 23, 2008 #2
    Note of is relation can be found at the first comment re the sequence 3,7,47 .... See http://www.research.att.com/~njas/sequences/A001566" [Broken], but I would like a proof if it is known.
    Last edited by a moderator: May 3, 2017
  4. Apr 23, 2008 #3
    These two identities should get you there.



    Where [tex]L_n[/tex] is the nth Lucas numbers.
  5. May 15, 2008 #4
    Where can I find a proof of those identities?
  6. May 17, 2008 #5
    Both identities can be proven using the closed form expressions for the Fibonacci and Lucas numbers. The closed form expressions should be easily accessible. The one for the Fibonacci numbers is also known as Binet's formula.
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