A337503 Minimum number of painted cells in an n X n grid to avoid unpainted pentominoes.

0, 0, 3, 5, 8, 13, 17, 24, 31, 39

Offset

1,3

Links

Table of n, a(n) for n=1..10.

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

Cf. A337501, A337502.

Sequence in context: A097431 A123929 A036715 * A310035 A310036 A265046

Adjacent sequences: A337500 A337501 A337502 * A337504 A337505 A337506

Keyword

nonn,more

Author

Rob Pratt, Aug 29 2020

Status

approved