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%I #14 Jul 31 2015 11:47:33
%S 2,8,25,67,165,387,881,1967,4333,9451,20457,44007,94181,200675,425953,
%T 901087,1900509,3997659,8388569,17563607,36700117,76546003,159383505,
%U 331349967,687865805,1426063307,2952789961,6106906567
%N (3*n+4)*2^(n-3)-(2*n-1).
%H Harry J. Smith, <a href="/A066374/b066374.txt">Table of n, a(n) for n = 2..200</a>
%H M. Azaola and F. Santos, <a href="http://personales.unican.es/santosf/Articulos/">The number of triangulations of the cyclic polytope C(n,n-4)</a>, Discrete Comput. Geom., 27 (2002), 29-48.
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (6, -13, 12, -4).
%F G.f.: x^2*(2-4*x+3*x^2-3*x^3)/((1-x)^2*(1-2*x)^2). [_Colin Barker_, Apr 20 2012]
%F a(2)=2, a(3)=8, a(4)=25, a(5)=67, a(n)=6*a(n-1)-13*a(n-2)+12*a(n-3)- 4*a(n-4). - _Harvey P. Dale_, Oct 23 2013
%t Table[(3n+4)2^(n-3)-(2n-1),{n,2,30}] (* or *) LinearRecurrence[ {6,-13,12,-4},{2,8,25,67},30] (* _Harvey P. Dale_, Oct 23 2013 *)
%o (PARI) { for (n=2, 200, write("b066374.txt", n, " ", (3*n + 4)*2^(n -3 ) - (2*n - 1)) ) } [_Harry J. Smith_, Feb 11 2010]
%K nonn,easy
%O 2,1
%A _N. J. A. Sloane_, Jan 04 2002
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