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%I #5 Jul 18 2013 02:53:02
%S 4797,135138,2268072,25678020,224320572,1649999532,10785747852,
%T 64824941388,366263505612,1974734612940,10266404558796,51852359848908,
%U 255825084304332,1238033348475852,5895322649598924,27690990109023180,128550270229863372,590735658025999308
%N The hyper-Wiener index of the nanostar dendrimer D_n, defined pictorially as NS[n] in the Yang et al. reference.
%C a(2) has been checked by the direct computation of the Wiener index (using Maple).
%D L. Yang, Connectivity, PI and vertex-Pi indices and polynomials of an infinite class of dendrimer nanostars, International J. Physical Sciences, 7(9), 2012, 1420-1423.
%F a(n) = - 140340 + 2^n*(82764*n^2 - 268092*n - 1159017) + 4^n*(156816*n^2 - 719928*n + 1304154).
%F G.f.: 3*(1599 + 14665*x + 140000*x^2 - 65180*x^3 - 605152*x^4 -886208*x^5 + 137216*x^6)/((1-x)*(1-2*x)^3*(1-4*x)^3).
%p a := proc (n) options operator, arrow: -140340+2^n*(82764*n^2-268092*n-1159017)+4^n*(156816*n^2-719928*n+1304154) end proc: seq(a(n), n = 0 .. 22);
%Y Cf. A227494.
%K nonn,easy
%O 1,1
%A _Emeric Deutsch_, Jul 17 2013
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