A337501 - OEIS

A337501

Minimum number of painted cells in an n X n grid to avoid unpainted trominoes.

0, 2, 4, 8, 11, 18, 23, 32, 39, 50

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

EXAMPLE

For n = 3, painting only 3 cells would leave an unpainted tromino, but painting the following 4 cells avoids all unpainted trominoes:

. . X

X X .

. . X

CROSSREFS

KEYWORD

nonn,more

AUTHOR

Rob Pratt, Aug 29 2020

STATUS

approved