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A221002 The Wiener index of the nanostar dendrimer G[n], defined pictorially in the Karbasioun-Ashrafi reference. 1
21558, 141686, 825078, 4438006, 22578678, 110311926, 522899958, 2422104566, 11019370998, 49421451766, 219106574838, 962208334326, 4192177750518, 18142557897206, 78066631049718, 334254292599286, 1424972878709238, 6051724204704246, 25614248465924598, 108086444576211446, 454863674100679158 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
LINKS
A. Karbasioun and A. R. Ashrafi, Wiener and detour indices of a new type of nanostar dendrimers, Macedonian J. of Chemistry and Chemical Engineering 28 (2009) 49-54.
FORMULA
a(n) = 502 + 2^(n+6)*5*(14*n+53)+4^(n+6)*(5n+1).
G.f.: -2*(84672*x^4-205344*x^3+181436*x^2-69284*x+10779) / ((x-1)*(2*x-1)^2*(4*x-1)^2). [Colin Barker, Jan 01 2013]
MAPLE
a := proc (n) options operator, arrow: 502+5*2^(n+6)*(14*n+53)+4^(n+6)*(5*n+1) end proc; :seq(a(n), n = 0 .. 20);
MATHEMATICA
LinearRecurrence[{13, -64, 148, -160, 64}, {21558, 141686, 825078, 4438006, 22578678}, 30] (* Harvey P. Dale, Jul 20 2019 *)
CROSSREFS
Cf. A221003.
Sequence in context: A063388 A252393 A211236 * A190470 A113620 A074812
KEYWORD
nonn,easy
AUTHOR
Emeric Deutsch, Dec 28 2012
STATUS
approved

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Last modified June 20 12:17 EDT 2024. Contains 373527 sequences. (Running on oeis4.)