login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A072153 Coordination sequence for VPl-5 structure with respect to node (Y) where 18-gon, hexagon and square meet. 2
1, 3, 5, 6, 7, 9, 11, 13, 16, 19, 20, 20, 22, 25, 27, 29, 32, 34, 34, 35, 38, 41, 43, 45, 47, 48, 49, 51, 54, 57, 59, 60, 61, 63, 65, 67, 70, 73, 74, 74, 76, 79, 81, 83, 86, 88, 88, 89, 92, 95, 97, 99, 101, 102, 103, 105, 108, 111, 113, 114, 115, 117, 119, 121, 124 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

There are two types of nodes in this structure.

The coordination sequence with respect to a particular node gives the number of nodes that can be reached from that node in n steps along edges.

REFERENCES

M. E. Davis, Ordered porous materials for emerging applications, Nature, 417 (Jun 20 2002), 813-821 (gives structure).

LINKS

Joseph Myers, Table of n, a(n) for n = 0..1000

N. J. A. Sloane, VPl-5 structure, after Davis

FORMULA

Empirical G.f.: (x^2+x+1)^2*(x^6+x^3+1)/((x-1)^2*(x^2+1)*(x^6+x^5+x^4+x^3+x^2+x+1)). [Colin Barker, Nov 18 2012]

CROSSREFS

Cf. A072149-A072154.

Sequence in context: A229089 A277573 A328585 * A206929 A331546 A230060

Adjacent sequences: A072150 A072151 A072152 * A072154 A072155 A072156

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Jun 28 2002

EXTENSIONS

Extended by Joseph Myers, Sep 30 2011

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 December 9 04:13 EST 2022. Contains 358698 sequences. (Running on oeis4.)