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A224423 The Wiener index of the Micelle-like chiral dendrimer G[n] defined pictorially in the Hassan Yousefi-Azari et al. reference. 1
24485, 120741, 613541, 3078309, 15070373, 71955621, 336069797, 1540900005, 6958417061, 31031755941, 136961328293, 599275078821, 2603021763749, 11236212212901, 48242297406629, 206161018094757, 877415731561637, 3720758807233701, 15727438348682405 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
COMMENTS
a(0) has been checked by the direct computation of the Wiener index (using Maple).
LINKS
H. Yousefi-Azari, A. R. Ashrafi, and M. H. Khalifeh, Wiener index of micelle-like chiral dendrimers, Studia UBB, Chemia, 55, No. 4, 125-130, 2010.
FORMULA
a(n) = 1189 + 15616*2^n + 7680*4^n + 12288*n*4^n + 4224*n*2^n (agrees with Theorem 2 of the Yousefi-Azari et al. reference).
G.f.: (24485-197564*x+610948*x^2-794080*x^3+366912*x^4)/((1-x)*(1-2*x)^2*(1-4*x)^2). [Bruno Berselli, Apr 06 2013]
MAPLE
a := proc (n) options operator, arrow: 1189 + 15616*2^n + 4224*2^n*n + 12288*4^n*n + 7680*4^n end proc: seq(a(n), n = 0 .. 18);
MATHEMATICA
CoefficientList[Series[(24485 - 197564 x + 610948 x^2 - 794080 x^3 + 366912 x^4)/((1 - x) (1 - 2 x)^2 (1 - 4 x)^2), {x, 0, 20}], x] (* Bruno Berselli, Apr 06 2013 *)
CROSSREFS
Cf. A224424.
Sequence in context: A083621 A083622 A237207 * A356355 A258441 A244150
KEYWORD
nonn,easy
AUTHOR
Emeric Deutsch, Apr 06 2013
STATUS
approved

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Last modified June 14 02:27 EDT 2024. Contains 373392 sequences. (Running on oeis4.)