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 A101351 #25 Dec 07 2019 12:18:24 %S A101351 2,4,9,18,36,71,140,276,545,1078,2136,4239,8424,16760,33377,66522, %T A101351 132668,264727,528468,1055340,2108097,4212014,8417264,16823583, %U A101351 33629456,67230256,134414145,268753266,537385140,1074573863,2148829916,4297145604,8593459169 %N A101351 a(n) = 2^n-1 + Fibonacci(n). %H A101351 Colin Barker, <a href="/A101351/b101351.txt">Table of n, a(n) for n = 1..1000</a> %H A101351 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-4,-1,2). %F A101351 a(n) = 4*a(n-1) -4*a(n-2) -a(n-3) +2*a(n-4). G.f.: x*(2-4*x+x^2)/((x-1) * (2*x-1) * (1-x-x^2)). - _R. J. Mathar_, Feb 06 2010 %F A101351 a(n) = ((1+sqrt(5))^n-(1-sqrt(5))^n)/(2^n*sqrt(5)) + 2^n - 1. - _Colin Barker_, Nov 02 2016 %p A101351 seq(2^x-1+fibonacci(x),x=1..30); %t A101351 Table[2^n-1+Fibonacci[n],{n,30}] (* or *) LinearRecurrence[{4,-4,-1,2},{2,4,9,18},30] (* _Harvey P. Dale_, Aug 24 2012 *) %o A101351 (Sage) [gaussian_binomial(n,1,2)+fibonacci (n) for n in range(1,31)] # _Zerinvary Lajos_, May 29 2009 %o A101351 (PARI) Vec(x*(2-4*x+x^2)/((1-x)*(1-2*x)*(1-x-x^2)) + O(x^30)) \\ _Colin Barker_, Nov 02 2016 %Y A101351 Cf. A000045, A033138. %K A101351 nonn,easy %O A101351 1,1 %A A101351 _Jorge Coveiro_, Dec 25 2004 %E A101351 Offset changed to 1 by _Colin Barker_, Nov 02 2016