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 A350717 #62 Feb 01 2023 08:11:16
%S A350717 1,2,5,16,59,230,913,3644,14567,58258,233021,932072,3728275,14913086,
%T A350717 59652329,238609300,954437183,3817748714,15270994837,61083979328,
%U A350717 244335917291,977343669142,3909374676545,15637498706156,62549994824599,250199979298370,1000799917193453,4003199668773784
%N A350717 a(n) = 4*a(n-1) - n - 1, for n > 0, a(0) = 1.
%C A350717 Last digit (using 0 to 9) is of period 10: repeat [1, 2, 5, 6, 9, 0, 3, 4, 7, 8].
%H A350717 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (6,-9,4).
%F A350717 a(n) = (2^(2*n+1) + 3*n + 7)/9.
%F A350717 a(n) = 6*a(n-1) - 9*a(n-2) + 4*a(n-3), n >= 3.
%F A350717 a(n) = a(n-1) + A007583(n-1).
%F A350717 a(n) = 2*a(n-1) + A014825(n-1).
%F A350717 G.f.: (-2*x^2 + 4*x - 1)/((x - 1)^2*(4*x - 1)). - _Thomas Scheuerle_, Feb 03 2022
%F A350717 a(n) = -1 + 5*a(n-1) - 4*a(n-2), n >= 2.
%F A350717 a(n) = 1 + A160156(n-1), n >= 1.
%t A350717 LinearRecurrence[{6, -9, 4}, {1, 2, 5}, 28] (* _Amiram Eldar_, Feb 03 2022 *)
%o A350717 (PARI) a(n) = if (n, 4*a(n-1) - n - 1, 1); \\ _Michel Marcus_, Feb 03 2022
%o A350717 (Python)
%o A350717 print([(2**(2*n+1) + 3*n + 7)//9 for n in range(30)])
%o A350717 # _Gennady Eremin_, Feb 05 2022
%Y A350717 Cf. A007583 (first differences), A014825, A160156.
%K A350717 nonn,easy
%O A350717 0,2
%A A350717 _Paul Curtz_, Feb 03 2022
%E A350717 More terms from _Michel Marcus_, Feb 03 2022