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A216115
The Hyper-Wiener index of a link of n fullerenes C_{20} (see the Ghorbani and Hosseinzadeh reference).
1
1020, 11020, 39600, 99960, 208900, 386820, 657720, 1049200, 1592460, 2322300, 3277120, 4498920, 6033300, 7929460, 10240200, 13021920, 16334620, 20241900, 24810960, 30112600, 36221220, 43214820, 51175000, 60186960, 70339500, 81725020, 94439520, 108582600, 124257460, 141570900
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.
FORMULA
a(n) = 10*n*(15n^3 +70n^2 + 134n - 117).
G.f.: -20*x*(98*x^3-265*x^2+296*x+51)/(x-1)^5. [Colin Barker, Oct 31 2012]
MAPLE
seq(150*n^4+700*n^3+1340*n^2-1170*n, n=1..30);
CROSSREFS
Cf. A216114.
Sequence in context: A157510 A015160 A102925 * A024020 A069791 A167846
KEYWORD
nonn,easy
AUTHOR
Emeric Deutsch, Oct 28 2012
STATUS
approved