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A221008 The Wiener index of the nanostar dendrimer D_3[n] , defined pictorially in the Alikhani - Iranmanesh reference. 1
1026, 19458, 174762, 1170810, 6751386, 35653338, 177967962, 854830170, 3994246746, 18282889818, 82367580762, 366439242330, 1613682326106, 7046530103898, 30553522371162, 131684094835290, 564617195813466, 2409993639295578, 10246077161667162, 43408725425257050, 183332581536692826 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
LINKS
S. Alikhani and M. A. Iranmanesh, Eccentric connectivity polynomials of an infinite family of dendrimer, Digest J. Nanomaterials and Biostructures, 6 (2011) 253-257.
FORMULA
a(n) = -1446 + 2^n*12132+4^n*(8820*n-9660).
G.f.: 18*(57+454*x+212*x^2)/((1-x)*(1-2*x)*(1-4*x)^2). - Bruno Berselli, Dec 30 2012
MAPLE
a := proc (n) options operator, arrow: -1446+12132*2^n+4^n*(8820*n-9660) end proc: seq(a(n), n = 0 .. 20);
CROSSREFS
Cf. A221009.
Sequence in context: A031530 A004607 A361811 * A282254 A229332 A253710
KEYWORD
nonn,easy
AUTHOR
Emeric Deutsch, Dec 29 2012
STATUS
approved

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Last modified July 20 18:43 EDT 2024. Contains 374459 sequences. (Running on oeis4.)