login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A216107 The hyper-Wiener index of the tetrameric 1,3-adamantane TA(n) (see the Fath-Tabar et al. reference). 1
168, 1720, 6636, 17796, 38980, 74868, 131040, 213976, 331056, 490560, 701668, 974460, 1319916, 1749916, 2277240, 2915568, 3679480, 4584456, 5646876, 6884020, 8314068, 9956100, 11830096, 13956936, 16358400, 19057168, 22076820, 25441836, 29177596, 33310380 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The Hosoya-Wiener polynomial of TA(n) is n(10+12t+18t^2+12t^3+3t^4)+(1+3t+3t^2+3t^3)^2*(t^{3n+1}-nt^4+nt-1)/(t^3-1)^2.

LINKS

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

G. H. Fath-Tabar, A. Azad, and N. Elahinezhad, Some topological indices of tetrameric 1,3-adamantane, Iranian J. Math. Chemistry, 1, No. 1, 2010, 111-118.

Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1).

FORMULA

a(n) = (75n^4 +210n^3 + 229n^2-178n)/2.

G.f.: -4*x*(34*x^3-71*x^2+220*x+42)/(x-1)^5. [Colin Barker, Oct 31 2012]

MAPLE

seq((75*n^4+210*n^3+229*n^2-178*n)*(1/2), n=1..30);

MATHEMATICA

Table[(75n^4+210n^3+229n^2-178n)/2, {n, 30}] (* or *) LinearRecurrence[{5, -10, 10, -5, 1}, {168, 1720, 6636, 17796, 38980}, 30] (* Harvey P. Dale, Jan 01 2016 *)

CROSSREFS

Cf. A216106.

Sequence in context: A112551 A303622 A263121 * A235932 A235926 A279725

Adjacent sequences:  A216104 A216105 A216106 * A216108 A216109 A216110

KEYWORD

nonn,easy

AUTHOR

Emeric Deutsch, Oct 26 2012

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 21 11:42 EDT 2019. Contains 328296 sequences. (Running on oeis4.)