Consider the following recurrence relation:$$ \text{a} (n)=\text{a} (n-1)+\text{a} (n-8)\\ \text{with } \text{a}(i)=1 \text{ for } i=0 \dots 7 $$The ratio of successive terms approach the golden ratio \( \phi \) just as the terms in the Fibonacci sequence do. Naturally, the terms in the sequence take a while to grow larger. Here are the initial terms:
1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 14, 18, 23, 29, 36, 44, 53, 64, 78, 96, 119, 148, 184, 228, 281, 345, 423, 519, 638, 786, 970, 1198, 1479, 1824, 2247, 2766, 3404, 4190, 5160, 6358, 7837, 9661, 11908, 14674, 18078, 22268, 27428, 33786, 41623
These terms form OEIS A005710. The generating function (permalink) for this sequence is:$$ \frac{1}{1-x-x^8}$$In general, we have:$$a(n) = a(n-1) + a(n-m) \\ \text{ with } a(n) = 1 \text{ for } n = 0 \dots m-1$$The generating function is:$$ \frac{1}{1-x-x^m}$$In the case of \(m=2\), we get the terms in the Fibonacci sequence.
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