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A227699 The Wiener index of the nanostar dendrimer defined pictorially in the Ashrafi et al. reference. 1

%I #13 May 16 2018 13:25:54

%S 34081,133753,606505,2879881,13759561,65105353,303499465,1393200841,

%T 6306020041,28195082953,124751348425,547085017801,2381092856521,

%U 10296337572553,44275297821385,189465493250761,807328896525001,3427204095550153

%N The Wiener index of the nanostar dendrimer defined pictorially in the Ashrafi et al. reference.

%C a(1) has been checked by the direct computation of the Wiener index (using Maple).

%H A. R. Ashrafi, A. Karbasioun, and M. V. Diudea, <a href="http://match.pmf.kg.ac.rs/electronic_versions/Match65/n1/match65n1_193-200.pdf">Computing Wiener and detour indices of a new type of nanostar dendrimers</a>, MATCH Commun. Math. Comput. Chem. 65, 2011, 193-200.

%F a(n) = 8905 + 2^(n)*(10560*n + 21528) + 4^(n)*(11520*n + 3648). Replacing n with n+1, we obtain the expression given in Theorem 1 of the Ashrafi et al. reference.

%F G.f.: (34081 - 309300*x + 1048900*x^2 - 1488480*x^3 + 794944*x^4)/((1-x)*(1-2*x)^2*(1-4*x)^2).

%p a := proc (n) options operator, arrow: 8905+2^n*(10560*n+21528)+4^n*(11520*n+3648) end proc: seq(a(n), n = 0 .. 22);

%Y Cf. A227700.

%K nonn

%O 0,1

%A _Emeric Deutsch_, Jul 21 2013

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Last modified March 28 04:13 EDT 2024. Contains 371235 sequences. (Running on oeis4.)