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%I #5 Jul 18 2013 02:54:11
%S 1437,18915,170799,1224231,7577943,42506295,222662391,1110797943,
%T 5346791799,25055240055,115015961463,519520043895,2316518945655,
%U 10221182047095,44708102116215,194132294964087,837742493569911,3595852736893815
%N The 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) = 4983 + 2^n*(15048*n + 29502) + 4^n*(14256*n - 33048).
%F G.f.: 3*(479 + 78*x + 5624*x^2 + 576*x^3 + 8192*x^4)/((1-x)*(1-2*x)^2*(1-4*x)^2).
%p a := proc (n) options operator, arrow: 4983+2^n*(15048*n+29502)+4^n*(14256*n-33048) end proc: seq(a(n), n = 0 .. 20);
%Y Cf. A227495.
%K nonn,easy
%O 0,1
%A _Emeric Deutsch_, Jul 17 2013