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 A114958 #14 Sep 08 2022 08:45:23 %S A114958 3,10,29,72,163,350,729,1492,3023,6090,12229,24512,49083,98230,196529, %T A114958 393132,786343,1572770,3145629,6291352,12582803,25165710,50331529, %U A114958 100663172,201326463,402653050,805306229,1610612592,3221225323 %N A114958 a(n) = 6*2^(n+1) - 5*(n+1) - 4. %H A114958 Vincenzo Librandi, <a href="/A114958/b114958.txt">Table of n, a(n) for n = 0..1000</a> %H A114958 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (4,-5,2). %F A114958 From _Colin Barker_, Apr 30 2019: (Start) %F A114958 G.f.: (3 - 2*x + 4*x^2) / ((1 - x)^2*(1 - 2*x)). %F A114958 a(n) = 4*a(n-1) - 5*a(n-2) + 2*a(n-3) for n>2. %F A114958 (End) %o A114958 (Magma) [6*2^(n+1) - 5*(n+1) - 4: n in [0..30] ]; // _Vincenzo Librandi_, May 18 2011 %o A114958 (PARI) Vec((3 - 2*x + 4*x^2) / ((1 - x)^2*(1 - 2*x)) + O(x^40)) \\ _Colin Barker_, Apr 30 2019 %Y A114958 Cf. A098011, A042950, A110164, A101229, A058764, A087009, A111286, A007283. %K A114958 easy,nonn %O A114958 0,1 %A A114958 _Creighton Dement_, Feb 21 2006