A224464 The hyper-Wiener index of the tetrathiafulvalene dendrimer defined pictorially as D[n] in the Shabani reference.

70159, 5540677, 94770993, 962654441, 7544225177, 50760280441, 309334151737, 1759763688889, 9520613312697, 49581897574073, 250630474019513, 1236980426140345, 5986802543205049, 28507052162513593, 133885149461756601

Offset

1,1

References

H. Shabani, Computing vertex PI index of tetrathiafulvalene dendrimers, Iranian J. Math. Chem., 1, 2010, 125-130.

Links

Table of n, a(n) for n=1..15.

Formula

a(n) = 1489593 + 2^n*(-190960*n^2 +743480*n - 13082162)+4^n*(3013696*n^2 - 7398832*n + 11662728).

G.f. =(70159 + 4207656*z + 21980*z^2 - 51514000*z^3 + 55017216*z^4 + 32361728*z^5 + 54272*z^6)/((1-z)*(1-2*z)^3*(1-4*z)^3).

Maple

a:= proc (n) options operator, arrow: 1489593+2^n*(-190960*n^2+743480*n-13082162)+4^n*(3013696*n^2-7398832*n+11662728) end proc: seq(a(n), n = 0 .. 14);

Crossrefs

Cf. A224463

Sequence in context: A043600 A043858 A043876 * A233987 A243135 A253738

Adjacent sequences: A224461 A224462 A224463 * A224465 A224466 A224467

Keyword

nonn

Author

Emeric Deutsch, Jul 12 2013

Status

approved