OFFSET
1,1
COMMENTS
a(2) has been checked by the direct computation of the Wiener index (using Maple).
The given references do not consider the Wiener index.
LINKS
Colin Barker, Table of n, a(n) for n = 1..1000
A. R. Ashrafi and P. Nikzad, Szeged index of nanostar dendrimers, Digest J. of Nanomaterials and Biostructures, 4, No. 1, 2009, 155-157.
M. Rostami, M. Shabanian, and H. Moghanian, Some topological indices for theoretical study of two types of nanostar dendrimers, Digest J. of Nanomaterials and Biostructures, 7, No. 1, 2012, 247-252.
Index entries for linear recurrences with constant coefficients, signature (13,-64,148,-160,64).
FORMULA
a(n) = -14237 + 46170*2^n - 32004*4^n +12960*n*4^n +72*n*2^n.
G.f.: x*(4544*x^4+144096*x^3+28316*x^2-46752*x-2071) / ((x-1)*(2*x-1)^2*(4*x-1)^2). - Colin Barker, Mar 31 2013
MAPLE
a := proc(n) -14237+46170*2^n-32004*4^n+12960*4^n*n+72*2^n*n end proc: seq(a(n), n = 1 .. 18);
PROG
(PARI) Vec(x*(4544*x^4+144096*x^3+28316*x^2-46752*x-2071)/((x-1)*(2*x-1)^2*(4*x-1)^2) + O(x^20)) \\ Colin Barker, Jun 04 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Emeric Deutsch, Mar 28 2013
STATUS
approved