A258186 a(n) is the maximal number of circles that can be enclosed by a closed chain of n circles; all circles' centers lie at coordinate points of the planar net 6.6.6.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 6, 6, 7, 7, 10, 10, 13

Offset: 0

Author

Kival Ngaokrajang, May 23 2015

Keywords

• nonn
• more

Comments

Inspired by A257594, in which the centers of circles can be considered to be placed on coordinate points of the planar net 3.3.3.3.3.3. See illustrations in the links.

Links

• Kival Ngaokrajang, Illustration for n = 0..11, for n = 12..22

Crossrefs

Cf. A257594.