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 A118263 #22 Sep 13 2024 00:39:54
%S A118263 1,1,1,2,3,4,4,9,16,8,27,64,16,81,256,32,243,1024,64,729,4096,128,
%T A118263 2187,16384,256,6561,65536,512,19683,262144,1024,59049,1048576,2048,
%U A118263 177147,4194304,4096,531441,16777216,8192,1594323,67108864,16384,4782969
%N A118263 a(3n) = 2^n, a(3n+1) = 3^n, a(3n+2) = 4^n.
%H A118263 Harvey P. Dale, <a href="/A118263/b118263.txt">Table of n, a(n) for n = 0..1000</a>
%H A118263 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,9,0,0,-26,0,0,24).
%F A118263 From _R. J. Mathar_, Mar 01 2010: (Start)
%F A118263 a(n) = 9*a(n-3) - 26*a(n-6) + 24*a(n-9).
%F A118263 G.f.: -(1+x+x^2-7*x^3-6*x^4-5*x^5+12*x^6+8*x^7+6*x^8) / ((3*x^3-1) * (2*x^3-1) * (4*x^3-1)). (End)
%t A118263 Table[{2^Floor[n/3], 3^Floor[n/3], 4^Floor[n/3]}[[Mod[n, 3] + 1]], {n, 0, 100}] (* _Olivier Gérard_, Sep 20 2007 *)
%t A118263 LinearRecurrence[{0,0,9,0,0,-26,0,0,24},{1,1,1,2,3,4,4,9,16},60] (* _Harvey P. Dale_, Jan 30 2021 *)
%K A118263 nonn,easy
%O A118263 0,4
%A A118263 _Hans Isdahl_, Sep 20 2007
%E A118263 More terms from _Olivier Gérard_, Sep 20 2007