OFFSET
0,9
COMMENTS
Examples of well-connected polyominoes are rectangles and loops:
.
XXXX
XXXX (rectangle)
.
XXX
X X (loop)
XXX
LINKS
EXAMPLE
a(4) = 1 because the 2 X 2 square polyomino is the only tetromino to be well-connected. The removal of any single square always results in an intact tromino. In each of the other 4 tetrominoes, there is a square whose removal would result in something that is not an intact polyomino.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
John Mason, Feb 07 2021
STATUS
approved