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 A370481 #42 Apr 04 2024 02:11:27
%S A370481 33,102,311,940,2829,8498,25507,76536,229625,688894,2066703,6200132,
%T A370481 18600421,55801290,167403899,502211728,1506635217,4519905686,
%U A370481 13559717095,40679151324,122037454013,366112362082,1098337086291,3295011258920,9885033776809,29655101330478
%N A370481 a(0) = 33. a(n) = 3*a(n-1) + 2*n + 1 for n >= 1.
%C A370481 Last digit is of period 10: repeat [3, 2, 1, 0, 9, 8, 7, 6, 5, 4].
%H A370481 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (5,-7,3).
%F A370481 a(n) = 4*a(n-1) - 3*a(n-2) + 2 with a(0) = 33 and a(1) = 102 for n >= 2.
%F A370481 a(n) = 10*A237930(n) + 3 - n.
%F A370481 a(n) = 35*3^n - n - 2. - _Hugo Pfoertner_, Mar 31 2024
%e A370481 a(1) = 3*33 + 3 = 102, a(2) = 3*102 + 5 = 311.
%t A370481 LinearRecurrence[{5, -7, 3}, {33, 102, 311}, 26] (* _Amiram Eldar_, Apr 01 2024 *)
%Y A370481 Cf. A144396, A237930.
%K A370481 nonn,easy
%O A370481 0,1
%A A370481 _Paul Curtz_, Mar 31 2024