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A227699 The Wiener index of the nanostar dendrimer defined pictorially in the Ashrafi et al. reference. 1
34081, 133753, 606505, 2879881, 13759561, 65105353, 303499465, 1393200841, 6306020041, 28195082953, 124751348425, 547085017801, 2381092856521, 10296337572553, 44275297821385, 189465493250761, 807328896525001, 3427204095550153 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
COMMENTS
a(1) has been checked by the direct computation of the Wiener index (using Maple).
LINKS
A. R. Ashrafi, A. Karbasioun, and M. V. Diudea, Computing Wiener and detour indices of a new type of nanostar dendrimers, MATCH Commun. Math. Comput. Chem. 65, 2011, 193-200.
FORMULA
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.
G.f.: (34081 - 309300*x + 1048900*x^2 - 1488480*x^3 + 794944*x^4)/((1-x)*(1-2*x)^2*(1-4*x)^2).
MAPLE
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);
CROSSREFS
Cf. A227700.
Sequence in context: A212229 A204669 A344666 * A234820 A182292 A206214
KEYWORD
nonn
AUTHOR
Emeric Deutsch, Jul 21 2013
STATUS
approved

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Last modified April 19 02:28 EDT 2024. Contains 371782 sequences. (Running on oeis4.)