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A305266
a(n) = 14*2^n + 73.
3
87, 101, 129, 185, 297, 521, 969, 1865, 3657, 7241, 14409, 28745, 57417, 114761, 229449, 458825, 917577, 1835081, 3670089, 7340105, 14680137, 29360201, 58720329, 117440585, 234881097, 469762121, 939524169, 1879048265, 3758096457, 7516192841, 15032385609, 30064771145
OFFSET
0,1
COMMENTS
For n>=1, a(n) is the number of edges of the first type of dendrimer nanostar G[n], shown pictorially in the Iranmanesh et al. reference (Fig. 1).
LINKS
A. Iranmanesh, N. A. Gholami, Computing the Szeged index of two type dendrimer nanostars, Croatica Chemica Acta, 81, No. 2, 2008, 299-303.
FORMULA
G.f.: (87 - 160*x)/((1-x)(1-2*x)). - Vincenzo Librandi, May 30 2018
MAPLE
seq(14*2^n+73, n = 0..40);
MATHEMATICA
Table[14 2^n + 73, {n, 0, 35}] (* Vincenzo Librandi, May 30 2018 *)
LinearRecurrence[{3, -2}, {87, 101}, 40] (* Harvey P. Dale, Dec 07 2019 *)
PROG
(Magma) [14*2^n+73: n in [0..35]]; // Vincenzo Librandi, May 30 2018
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Emeric Deutsch, May 29 2018
STATUS
approved