I have been challenged to find the general term or the recurrence relation for this sequence
5,18,44,96,195.... The only hint I have is that this sequence is an applied Fibonacci sequence. Can someone please suggest ways to find the recurrence or the nth term. I have looked at OEIS but found no note this for this particular integer sequence. I have searched at numerous locations but have had no success. Also ,I think the terms of this sequence can be determined in logarithmic time. Any help will be highly appreciated.
A closed form of the sequence is
a(n) = (n*Luc(n+6) - 4*Fib(n))/5
where Luc(k)
is the k
-th Lucas number, and Fib(k)
the k
-th Fibonacci number. Since Luc(k) = Fib(k+1) + Fib(k-1)
, the formula can easily be rewritten to use only Fibonacci numbers.