OFFSET
0,8
COMMENTS
Each connected group of unoccupied lines in the hexagonal structure enclosed by toothpicks counts as a hole.
LINKS
EXAMPLE
Structure after step 8:
\_/
\_/ \_/
\_/ \_/ \_/
\_/ _/ \_ \_/
/ \_/ \_/ \_/ \
\_/ \_/ \_/ \_/
/ \ / \_/ \ / \
\_/ \_/ \_/ \_/
/ \_/ \_/ \_/ \
\_/ \_/ \_/ \_/
/ \_ \_/ _/ \
/ \_/ \_/ \
/ \_/ \
/ \
There are 6 holes in this structure, in each 1 toothpick is missing, so a(8)=6.
CROSSREFS
KEYWORD
nonn
AUTHOR
Olaf Voß, Jan 13 2011
STATUS
approved