A227482 The Wiener index of the nanostar dendrimer defined pictorially as NS[n] in the M. Mirzargar reference.

4644, 101007, 945783, 6458535, 37636839, 200044647, 1002825063, 4831285095, 22623961959, 103728982887, 467924253543, 2083881950055, 9184570923879, 40135063034727, 174128583269223, 750870085229415, 3220908204874599, 13753353986104167, 58492320032480103, 247884935325539175, 1047202439771446119

Offset

0,1

Links

Table of n, a(n) for n=0..20.

M. Mirzargar, PI, Szeged and edge Szeged polynomials of a dendrimer nanostar, MATCH, Commun. Math. Comput. Chem. 62, 2009, 363-370.

Formula

a(n) = -9369 +2^n*74088 +4^n*(50625*n-60075).

G.f.: 27*(172+1849*x+1102*x^2)/((1-x)*(1-2*x)*(1-4*x)^2).

Maple

a := proc (n) options operator, arrow: -9369+50625*4^n*n-60075*4^n+74088*2^n end proc: seq(a(n), n = 0 .. 20);

Crossrefs

Cf. A227483.

Sequence in context: A343637 A233855 A068268 * A028551 A031615 A122713

Adjacent sequences: A227479 A227480 A227481 * A227483 A227484 A227485

Keyword

nonn,easy

Author

Emeric Deutsch, Jul 13 2013

Status

approved