This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A157727 #25 Jul 22 2024 09:17:18 %S A157727 4,5,5,6,7,9,12,17,25,38,59,93,148,237,381,614,991,1601,2588,4185, %T A157727 6769,10950,17715,28661,46372,75029,121397,196422,317815,514233, %U A157727 832044,1346273,2178313,3524582,5702891,9227469,14930356,24157821,39088173,63245990,102334159 %N A157727 a(n) = Fibonacci(n) + 4. %H A157727 Vincenzo Librandi, <a href="/A157727/b157727.txt">Table of n, a(n) for n = 0..285</a> %H A157727 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 A157727 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (2,0,-1). %F A157727 a(0) = 4, a(1) = 5, a(n) = a(n - 2) + a(n - 1) - 4. - _Reinhard Zumkeller_, Jul 30 2013 %F A157727 G.f.: (4 - 3*x - 5*x^2)/((1 - x)*(1 - x - x^2)). - _Stefano Spezia_, Jul 21 2024 %t A157727 Fibonacci[Range[0,50]]+4 (* _Harvey P. Dale_, Jun 17 2011 *) %o A157727 (Magma) [ Fibonacci(n) + 4: n in [0..40] ]; // _Vincenzo Librandi_, Apr 24 2011 %o A157727 (PARI) a(n)=fibonacci(n)+4 \\ _Charles R Greathouse IV_, Jul 02 2013 %o A157727 (Haskell) %o A157727 a157727 = (+ 4) . a000045 %o A157727 a157727_list = 4 : 5 : map (subtract 4) %o A157727 (zipWith (+) a157727_list $ tail a157727_list) %o A157727 -- _Reinhard Zumkeller_, Jul 30 2013 %Y A157727 Cf. A000045, A001611, A000071, A157725, A001911, A157726, A006327, A157727, A157728, A157729, A167616. %K A157727 nonn,easy %O A157727 0,1 %A A157727 _N. J. A. Sloane_, Jun 26 2010