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A221009 The hyper-Wiener index of the nanostar dendrimer D_3[n] , defined pictorially in the Alikhani - Iranmanesh reference. 1
3393, 129171, 1802955, 16741275, 125055483, 817601211, 4890505275, 27466038075, 147217502523, 761318440251, 3827379655995, 18807535273275, 90701268968763, 430607210751291, 2017310632781115, 9343468205122875 (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) = 9531-2^n*168276+4^n*(44100*n^2-92190*n+162138).
G.f.: 3*(1131+26092*x+52396*x^2+6160*x^3)/((1-x)*(1-2*x)*(1-4*x)^3). - Bruno Berselli, Dec 30 2012
MAPLE
a := proc (n) options operator, arrow: 9531-168276*2^n+4^n*(44100*n^2-92190*n+162138) end proc: seq(a(n), n = 0 .. 15);
CROSSREFS
Sequence in context: A172788 A185573 A185926 * A226667 A206507 A133532
KEYWORD
nonn
AUTHOR
Emeric Deutsch, Dec 29 2012
EXTENSIONS
Formula corrected by Bruno Berselli, Dec 30 2012
STATUS
approved

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Last modified July 15 23:38 EDT 2024. Contains 374343 sequences. (Running on oeis4.)