OFFSET
1,3
LINKS
Puzzling Stack Exchange, Least number of marked symbols
EXAMPLE
For n = 3, painting only 2 cells would leave an unpainted pentomino, but painting the following 3 cells avoids all unpainted pentominoes:
. . .
. X X
X . .
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Rob Pratt, Aug 29 2020
STATUS
approved