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 A173150 #16 Jun 23 2018 12:19:24
%S A173150 0,0,288,235224,354079488,865363202000,3134808545188320,
%T A173150 15796198853361763368,105717380511014096025600,
%U A173150 907380314352243226001152800,9718304978537581699085289156000
%N A173150 a(n) = sinh^2 (2n*arccosh(sqrt n)).
%C A173150 Also a(n) = -sin(2n*arccos(sqrt(n)))^2 = -sin(2n*arcsin(sqrt(n)))^2.
%H A173150 Vincenzo Librandi, <a href="/A173150/b173150.txt">Table of n, a(n) for n = 0..170</a>
%p A173150 A173150 := proc(n) sinh(2*n*arccosh(sqrt(n))) ; %^2 ; expand(%) ; simplify(%) ;end proc: # _R. J. Mathar_, Feb 26 2011
%t A173150 Table[Round[-Sin[2 n ArcCos[Sqrt[n]]]^2], {n, 0, 20}] (* _Artur Jasinski_, Feb 11 2010 *)
%Y A173150 Cf. A132592, A146311, A146312, A146313, A173115, A173116, A173121, A173127, A173128, A173129, A173130, A173131, A173133, A173134, A173148.
%K A173150 nonn
%O A173150 0,3
%A A173150 _Artur Jasinski_, Feb 11 2010
%E A173150 Minor edits by _Vaclav Kotesovec_, Apr 05 2016