%I #12 Sep 08 2022 08:46:09
%S 2,3,17,74,319,1359,5770,24463,103661,439170,1860443,7881107,33385138,
%T 141422091,599074201,2537720026,10749956135,45537547527,192900151034,
%U 817138159415,3461452801237,14662949384658,62113250372707,263115950928619,1114577054173154
%N Lucas(3*n) - Fibonacci(n).
%H Vincenzo Librandi, <a href="/A245799/b245799.txt">Table of n, a(n) for n = 0..200</a>
%F G.f.: (2 - 7*x + 6*x^2 + 5*x^3)/((1 - x - x^2)(1 - 4*x - x^2)).
%t Table[LucasL[3 n] - Fibonacci[n], {n, 0, 30}] (* or *) CoefficientList[Series[(2 - 7 x + 6 x^2 + 5 x^3)/((1 - x - x^2) (1 - 4 x - x^2)), {x, 0, 40}], x]
%o (Magma) [Lucas(3*n) - Fibonacci(n): n in [0..30]];
%o (Python)
%o import sympy
%o {print(sympy.lucas(3*n)-sympy.fibonacci(n),end=', ') for n in range(50)}
%o # _Derek Orr_, Aug 02 2014
%Y Cf. A000032, A000045, A005248, A014448.
%K nonn,easy
%O 0,1
%A _Vincenzo Librandi_, Aug 02 2014
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