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 A094971 #13 Sep 08 2022 08:45:13
%S A094971 1,4,20,91,410,1845,8303,37366,168151,756680,3405062,15322783,
%T A094971 68952523,310286355,1396288601,6283298708,28274844190,127236798856,
%U A094971 572565594852,2576545176835,11594453295761,52175039830928,234787679239180
%N A094971 a(n) = floor(9^n/2^n).
%H A094971 Vincenzo Librandi, <a href="/A094971/b094971.txt">Table of n, a(n) for n = 0..900</a>
%t A094971 Table[ Floor[(9/2)^n], {n, 0, 30}]
%o A094971 (Magma) [Floor(9^n / 2^n): n in [0..30]]; // _Vincenzo Librandi_, Sep 08 2011
%o A094971 (PARI) a(n)=9^n>>n \\ _Charles R Greathouse IV_, Feb 04 2016
%Y A094971 Cf. A002379, A094969-A094999.
%K A094971 nonn,easy
%O A094971 0,2
%A A094971 _Robert G. Wilson v_, May 26 2004