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%I #22 Apr 18 2021 19:16:30
%S 40,112,240,448,760,1200,1792,2560,3528,4720,6160,7872,9880,12208,
%T 14880,17920,21352,25200,29488,34240,39480,45232,51520,58368,65800,
%U 73840,82512,91840,101848,112560,124000,136192,149160,162928,177520,192960,209272,226480,244608,263680
%N Molecular topological index of the n-antiprism graph.
%C Antiprism graphs are defined for n>=3; sequence extended to n=1 using closed form
%H Andrew Howroyd, <a href="/A192791/b192791.txt">Table of n, a(n) for n = 1..1000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/AntiprismGraph.html">Antiprism Graph</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/MolecularTopologicalIndex.html">Molecular Topological Index</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).
%F a(n) = 4*n*(n^2 + n + 8).
%F a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4).
%F G.f.: 8*x*(4*x^2-6*x+5)/(x-1)^4. - _Colin Barker_, Nov 04 2012
%t LinearRecurrence[{4,-6,4,-1},{40,112,240,448},40] (* _Harvey P. Dale_, Mar 29 2018 *)
%o (PARI) a(n) = {4*n*(n^2 + n + 8)} \\ _Andrew Howroyd_, Apr 18 2021
%Y Cf. A192838.
%K nonn,easy
%O 1,1
%A _Eric W. Weisstein_, Jul 10 2011
%E Terms a(31) and beyond from _Andrew Howroyd_, Apr 18 2021
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