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What is the value of F(6) (Posted on 2025-04-24)

If F(n) is a function that satisfies F(1)=F(2)=F(3)=1,with:

F(n+1)=(F(n)*F(n-1)+1)/F(n-2) whenever n>=3.
Find the value of F(6)

No Solution Yet Submitted by K Sengupta

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computer solution

Comment 1 of 1

F(6) = 7 as seen in the table produced below:

F=[1,1,1];

for n=3:15

F(n+1)=(F(n)*F(n-1)+1)/F(n-2);

end

[[1:16]' F']

tabulates the values of F(1) through F(16):

           1           1
           2           1
           3           1
           4           2
           5           3
           6           7
           7          11
           8          26
           9          41
          10          97
          11         153
          12         362
          13         571
          14        1351
          15        2131
          16        5042

This is A005246 in the OEIS.

Posted by Charlie on 2025-04-24 09:54:37

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