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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A098851 Number of triangle-free configurations of type (n_3). 3
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 4, 14, 162, 4713 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,18

REFERENCES

A. Betten, G. Brinkmann and T. Pisanski, Counting symmetric configurations v_3, Discrete Appl. Math., 99 (2000), 331-338.

M. Boben et al., Small triangle-free configurations of points and lines, Discrete Comput. Geom., 35 (2006), 405-427.

LINKS

Table of n, a(n) for n=1..21.

CROSSREFS

Cf. A001403.

Sequence in context: A162077 A247526 A111266 * A080986 A132555 A129220

Adjacent sequences:  A098848 A098849 A098850 * A098852 A098853 A098854

KEYWORD

nonn,hard

AUTHOR

N. J. A. Sloane.

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified March 29 13:17 EDT 2017. Contains 284270 sequences.