%I #29 Sep 08 2022 08:45:42
%S 3,4,4,5,6,8,11,16,24,37,58,92,147,236,380,613,990,1600,2587,4184,
%T 6768,10949,17714,28660,46371,75028,121396,196421,317814,514232,
%U 832043,1346272,2178312,3524581,5702890,9227468,14930355,24157820,39088172,63245989,102334158
%N a(n) = Fibonacci(n) + 3.
%H Vincenzo Librandi, <a href="/A157726/b157726.txt">Table of n, a(n) for n = 0..285</a>
%H Ivana Jovović and Branko Malešević, <a href="http://nntdm.net/volume-23-2017/number-1/28-38/">Some enumerations of non-trivial composition of the differential operations and the directional derivative</a>, Notes on Number Theory and Discrete Mathematics, Vol. 23, 2017, No. 1, 28-38.
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (2,0,-1).
%F G.f.: ( 3-2*x-4*x^2 ) / ( (x-1)*(x^2+x-1) ). - _R. J. Mathar_, Aug 08 2012
%F a(0) = 3, a(1) = 4, a(n) = a(n - 2) + a(n - 1) - 3. - _Reinhard Zumkeller_, Jul 30 2013
%t Fibonacci[Range[0,45]]+3 (* _Harvey P. Dale_, Oct 26 2011 *)
%o (Magma) [ Fibonacci(n) + 3: n in [0..40] ]; // _Vincenzo Librandi_, Apr 24 2011
%o (PARI) a(n)=fibonacci(n)+3 \\ _Charles R Greathouse IV_, Jul 02 2013
%o (Haskell)
%o a157726 = (+ 3) . a000045
%o a157726_list = 3 : 4 : map (subtract 3)
%o (zipWith (+) a157726_list $ tail a157726_list)
%o -- _Reinhard Zumkeller_, Jul 30 2013
%Y Cf. A000045, A001611, A000071, A157725, A001911, A157726, A006327, A157727, A157728, A157729, A167616.
%K nonn,easy
%O 0,1
%A _N. J. A. Sloane_, Jun 26 2010