OFFSET
1,18
LINKS
A. Alazemi and A. Betten, Classification of Triangle-Free 22_3 Configurations, International Journal of Combinatorics, Volume 2010, Article ID 767361.
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.
CROSSREFS
KEYWORD
nonn,more,hard
AUTHOR
EXTENSIONS
a(22) from Abdullah Alazemi, Sep 05 2021
STATUS
approved