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A102905 a(n) = A113655(Fibonacci(n+1)).

%I A102905 #14 Dec 09 2022 07:15:02
%S A102905 3,3,2,1,5,8,15,19,36,57,89,142,233,377,612,985,1599,2586,4181,6763,
%T A102905 10946,17711,28659,46366,75027,121395,196418,317809,514229,832040,
%U A102905 1346271,2178307,3524580,5702889,9227465,14930350,24157817,39088169
%N A102905 a(n) = A113655(Fibonacci(n+1)).
%H A102905 G. C. Greubel, <a href="/A102905/b102905.txt">Table of n, a(n) for n = 0..1000</a>
%H A102905 <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,0,0,0,0,0,1,-1,-1).
%F A102905 a(n) = f(Fibonacci(n+1)), where f(n) = n-2 if (n mod 3) = 0, f(n) = n+2 if (n mod 3) = 1, otherwise f(n) = n.
%F A102905 a(n) = A113655(Fibonacci(n+1)).
%F A102905 G.f.: (3-4*x^2-4*x^3+2*x^4+2*x^5+2*x^6-4*x^7-x^8+2*x^9) / ((1-x)*(1+x)*(1+x^2)*(1-x-x^2)*(1+x^4)). - _Colin Barker_, Dec 11 2012
%F A102905 a(n) = (1 + 3*(-1)^n)/4 + Fibonacci(n+1) + (3/2)*(-1)^floor(n/2) * (n mod  2) + A014017(n) + A014017(n-1) - A014017(n-2). - _G. C. Greubel_, Dec 09 2022
%t A102905 f[n_]:= If[Mod[n,3]==0, n-2, If[Mod[n,3]==1, n+2, n]]; (* f=A113655 *)
%t A102905 Table[f[Fibonacci[n+1]], {n,0,50}]
%o A102905 (Magma)
%o A102905 A113655:= func< n | 6*Floor((n+2)/3) -(n+2) >;
%o A102905 A102905:= func< n | A113655(Fibonacci(n+1)) >;
%o A102905 [A102905(n): n in [0..50]]; // _G. C. Greubel_, Dec 09 2022
%o A102905 (SageMath)
%o A102905 def A113655(n): return 6*((n+2)//3) -(n+2)
%o A102905 def A102905(n): return A113655(fibonacci(n+1))
%o A102905 [A102905(n) for n in range(51)] # _G. C. Greubel_, Dec 09 2022
%Y A102905 Cf. A000045, A014017, A113655.
%K A102905 nonn
%O A102905 0,1
%A A102905 _Roger L. Bagula_, Mar 16 2005
%E A102905 Edited by _G. C. Greubel_, Dec 09 2022