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 A155600 #28 Jul 19 2024 15:48:11
%S A155600 1,8,78,722,6546,59018,531378,4782842,43046466,387419978,3486783378,
%T A155600 31381057562,282429532386,2541865820138,22876792438578,
%U A155600 205891132061882,1853020188786306,16677181699535498,150094635296736978
%N A155600 a(n) = 9^n-2^n+1^n.
%H A155600 Paolo Xausa, <a href="/A155600/b155600.txt">Table of n, a(n) for n = 0..1000</a>
%H A155600 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (12,-29,18).
%F A155600 G.f.: 1/(1-9*x)-1/(1-2*x)+1/(1-x). E.g.f.: e^(9*x)-e^(2*x)+e^x.
%F A155600 a(n) = 11*a(n-1)-18*a(n-2)+8 with a(0)=1, a(1)=8 - _Vincenzo Librandi_, Jul 21 2010
%F A155600 a(n) = A191465(n)+1. - _R. J. Mathar_, Mar 10 2022
%t A155600 Table[9^n - 2^n + 1, {n, 0, 25}] (* or *)
%t A155600 LinearRecurrence[{12, -29, 18}, {1, 8, 78}, 26] (* _Paolo Xausa_, Jul 19 2024 *)
%o A155600 (PARI) a(n)=9^n-2^n+1 \\ _Charles R Greathouse IV_, Sep 24 2015
%Y A155600 Cf. A074501, A020515, A155588, A155590, A155592, A155593, A155594, A155596, A155597, A155598, A155599.
%K A155600 nonn,easy
%O A155600 0,2
%A A155600 _Mohammad K. Azarian_, Jan 25 2009