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%I #21 Jun 23 2023 09:03:39
%S 5298,39854,251046,1422550,7507638,37673334,182185206,856903670,
%T 3945369078,17864129014,79813259766,352738009590,1545019376118,
%U 6716624699894,29013289140726,124641612792310,532923049312758,2269124503273974,9626239798084086,40703952922083830,171611842722922998
%N The Wiener index of the nanostar dendrimer defined pictorially as G[n] in the M. H. Khalifeh et al. reference.
%C a(0) and a(1) have been checked by the direct computation of the Wiener index (using Maple).
%H Matthew House, <a href="/A227486/b227486.txt">Table of n, a(n) for n = 0..1640</a>
%H M. K. Khalifeh, H. Yousefi-Azari, and A. R. Ashrafi, <a href="https://chalcogen.ro/1Khalifeh.pdf">The Szeged and Wiener numbers of water soluble polyaryl ether dendrimer nanostars</a>, Digest J. Nanomaterials and Biostructures, 4, 2009, 63-66.
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (13,-64,148,-160,64).
%F a(n) = 502 + 2^(n)*(2800*n + 8716) + 4^(n)*(8000*n - 3920).
%F G.f.: 2*(2649 - 14510*z + 36008*z^2 - 37248*z^3 + 15360*z^4)/((1-z)*(1-2*z)^2*(1-4*z)^2).
%F a(n) = 13*a(n-1) - 64*a(n-2) + 148*a(n-3) - 160*a(n-4) + 64*a(n-5). - _Matthew House_, Nov 01 2016
%p a := proc (n) options operator, arrow: 502+2^n*(2800*n+8716)+4^n*(8000*n-3920) end proc: seq(a(n), n = 0 .. 20);
%Y Cf. A227487
%K nonn
%O 0,1
%A _Emeric Deutsch_, Jul 13 2013
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