login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A044048 Catafusenes (see reference for precise definition). 1
1, 1, 3, 10, 37, 149, 630, 2713, 11899, 52789, 236345, 1066317, 4842531, 22117897, 101535659, 468233674, 2168094625, 10076216851, 46986691678, 219777820957, 1030892924479, 4848040645676, 22853639788127, 107970205586283 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

REFERENCES

S. J. Cyvin et al., Enumeration and classification of certain polygonal systems...: annelated catafusenes, J. Chem. Inform. Comput. Sci., 34 (1994), 1174-1180.

LINKS

Table of n, a(n) for n=0..23.

FORMULA

G.f.: [6-18x^3-(1-x)(1-2x)f(x)-3(1+2x)f(x^2)-2f(x^3)]/(12x^3), where f(x)=sqrt(1-6x+5x^2) (follows from eq. (26) in Cyvin et al.)

CROSSREFS

Sequence in context: A063029 A199874 A151058 * A192240 A231894 A086444

Adjacent sequences:  A044045 A044046 A044047 * A044049 A044050 A044051

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Emeric Deutsch, Mar 14 2004

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 April 9 16:39 EDT 2020. Contains 333361 sequences. (Running on oeis4.)