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 A020705 #19 Oct 30 2024 21:47:29 %S A020705 4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28, %T A020705 29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51, %U A020705 52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78 %N A020705 a(n) = n + 4. %C A020705 Pisot sequences E(4,5), P(4,5), T(4,5). %H A020705 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>. %H A020705 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1). %F A020705 a(n) = 2*a(n-1) - a(n-2). %F A020705 From _Elmo R. Oliveira_, Oct 30 2024: (Start) %F A020705 G.f.: (4 - 3*x)/(1 - x)^2. %F A020705 E.g.f.: (4 + x)*exp(x). %F A020705 a(n) = A020744(n)/2 = A055999(n+1) - A055999(n). (End) %t A020705 Range[4, 100] (* _Wesley Ivan Hurt_, May 17 2023 *) %o A020705 (PARI) a(n)=n+4 %Y A020705 See A008776 for definitions of Pisot sequences. %Y A020705 Cf. A020744, A055999. %K A020705 nonn,easy %O A020705 0,1 %A A020705 _David W. Wilson_