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 hyper-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 (19,-150,636,-1560,2208,-1664,512).
FORMULA
a(n) = 204780 - 1311272*2^n + 1106480*4^n + 360*2^n*n^2 + 129600*4^n*n^2 + 7852*2^n*n - 633600*4^n*n.
G.f.: 4*x*(1536*x^6-1645696*x^5-1592416*x^4+2192808*x^3-189320*x^2 -147032*x -2145) / ((x-1)*(2*x-1)^3*(4*x-1)^3). - Colin Barker, Apr 01 2013
MAPLE
a := proc(n) 204780-1311272*2^n+1106480*4^n+360*2^n*n^2+129600*4^n*n^2 +7852*2^n*n-633600*4^n*n end proc: seq(a(n), n = 1 .. 17);
PROG
(PARI) Vec(4*x*(1536*x^6-1645696*x^5-1592416*x^4+2192808*x^3-189320*x^2 -147032*x-2145)/((x-1)*(2*x-1)^3*(4*x-1)^3) + O(x^20)) \\ Colin Barker, Jun 04 2016
CROSSREFS
Cf. A221052.
KEYWORD
nonn,easy
AUTHOR
Emeric Deutsch, Mar 28 2013
STATUS
approved