A216114 The Wiener index of a link of n fullerenes C_{20} (see the Ghorbani and Hosseinzadeh reference).

500, 3400, 9900, 21200, 38500, 63000, 95900, 138400, 191700, 257000, 335500, 428400, 536900, 662200, 805500, 968000, 1150900, 1355400, 1582700, 1834000, 2110500, 2413400, 2743900, 3103200, 3492500, 3913000, 4365900, 4852400, 5373700, 5931000

Offset

1,1

Comments

The Hosoya-Wiener polynomial of the graph is nw + r^2*(t^{3n+1}-nt^4+nt-t)/(t^3-1)^2, where w=20+30t+60t^2+60t^3+30t^4+10t^5 and r=1+3t+6t^2+6t^3+3t^4+t^5.

References

M. Ghorbani and M. A. Hosseinzadeh, On Wiener index of special case of link fullerenes, Optoelectronics and advanced materials - Rapid Communications, 4, 2010, 538-539.

Links

Table of n, a(n) for n=1..30.

Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).

Formula

a(n) = 100*n*(2n^2 + 6n - 3).

G.f.: -100*x*(7*x^2-14*x-5)/(x-1)^4. [Colin Barker, Oct 31 2012]

Maple

seq(200*n^3+600*n^2-300*n, n=1..30);

Mathematica

LinearRecurrence[{4, -6, 4, -1}, {500, 3400, 9900, 21200}, 30] (* Harvey P. Dale, Oct 20 2024 *)

Crossrefs

Cf. A216115.

Sequence in context: A372864 A045215 A194085 * A005954 A333137 A281779

Adjacent sequences: A216111 A216112 A216113 * A216115 A216116 A216117

Keyword

nonn,easy

Author

Emeric Deutsch, Oct 28 2012

Status

approved