The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A221003 The hyper-Wiener index of the nanostar dendrimer G[n], defined pictorially in the Karbasioun-Ashrafi reference. 1
192133, 1790789, 13716357, 92392837, 568494213, 3272754309, 17914312837, 94292506757, 481127721093, 2394073245829, 11669512054917, 55910670854277, 264011366000773, 1231270134409349, 5680970473662597, 25967383211403397 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
LINKS
A. Karbasioun and A. R. Ashrafi, Wiener and detour indices of a new type of nanostar dendrimers, Macedonian J. of Chemistry and Chemical Engineering 28 (2009) 49-54.
Index entries for linear recurrences with constant coefficients, signature (19,-150,636,-1560,2208,-1664,512).
FORMULA
a(n) = -6011 + 2^n*(11200*n^2 + 5920*n - 177792) + 4^n*(102400*n^2 + 51200*n + 375936).
G.f.: (7432704*x^6 -23912064*x^5 +31269536*x^4 -21796184*x^3 +8511316*x^2 -1859738*x +192133) / ((x-1)*(2*x-1)^3*(4*x-1)^3). [Colin Barker, Jan 01 2013]
MAPLE
a := proc (n) options operator, arrow: -6011+2^n*(11200*n^2+5920*n-177792)+4^n*(102400*n^2+51200*n+375936) end proc: seq(a(n), n = 0 .. 15);
CROSSREFS
Cf. A221002.
Sequence in context: A256768 A186584 A178289 * A206619 A253522 A254420
KEYWORD
nonn,easy
AUTHOR
Emeric Deutsch, Dec 28 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 19 08:13 EDT 2024. Contains 372666 sequences. (Running on oeis4.)