

A224432


The hyperWiener index of the dendrimer D_2[n], defined pictorially in the A. R. Ashrafi et al. reference.


1



622, 28413, 426343, 4177227, 32549395, 220006179, 1351039555, 7748170371, 42234607363, 221419948035, 1125752748547, 5584044867075, 27143513179651, 129736439305731, 611327539426819, 2845765137102339, 13108587035424259, 59831264715339267
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OFFSET

0,1


COMMENTS

a(2) has been checked by the direct computation of the hyperWiener index (using Maple).


REFERENCES

A. R. Ashrafi and H. Shabani, Computing PadmakarIvan index of four classes of dendrimers, Bulgarian Chem. Comm., 44, N0. 2, 2012, 127130.


LINKS

Table of n, a(n) for n=0..17.


FORMULA

a(n) =  2557  76735*2^n  9768*2^n*n  44640*4^n*n + 79914*4^n + 14400*4^n*n^2 + 2640*2^n*n^2.
G.f.=(622+16595z20204z^256932z^3+33184z^451520z^5+9216z^6)/[(1z)(12z)^3(14z)^3].


MAPLE

a := proc (n) options operator, arrow: 255776735*2^n9768*2^n*n44640*4^n*n+79914*4^n+14400*4^n*n^2+2640*2^n*n^2 end proc: seq(a(n), n = 0 .. 17);


CROSSREFS

Cf. A224431
Sequence in context: A251243 A184226 A260764 * A229318 A268025 A207554
Adjacent sequences: A224429 A224430 A224431 * A224433 A224434 A224435


KEYWORD

nonn


AUTHOR

Emeric Deutsch, Apr 06 2013


STATUS

approved



