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 A132727 #10 Feb 14 2021 21:41:04
%S A132727 1,3,18,216,5184,248832,23887872,4586471424,1761205026816,
%T A132727 1352605460594688,2077601987473440768,6382393305518410039296,
%U A132727 39213424469105111281434624,481854559876363607426268659712
%N A132727 a(n) = 3 * 2^(n-1) * a(n-1) with a(0) = 1.
%C A132727 Power sequence relate to the Pythagorean musical scale: v(n,m) = v[0] * (3 * 2^n * m) starting at m = 1: a(n) = 3 * 2^(n-1) * a(n-1).
%C A132727 Hankel transform of A089022 with interpolated zeros. - _Paul Barry_, Mar 17 2008
%H A132727 G. C. Greubel, <a href="/A132727/b132727.txt">Table of n, a(n) for n = 0..80</a>
%F A132727 a(n) = 3^n * 2^binomial(n,2). - _Paul Barry_, Mar 17 2008
%t A132727 a[n_]:= a[n]= If[n<2, 2^(n+1) -1, 3*2^(n-1)*a[n-1]]; Table[a[n], {n, 0, 20}]
%o A132727 (Sage) [3^n*2^binomial(n, 2) for n in (0..20)] # _G. C. Greubel_, Feb 14 2021
%o A132727 (Magma) [3^n*2^Binomial(n, 2): n in [0..20]]; // _G. C. Greubel_, Feb 14 2021
%K A132727 nonn
%O A132727 0,2
%A A132727 _Roger L. Bagula_, Nov 17 2007
%E A132727 Offset changed by _G. C. Greubel_, Feb 14 2021