A145997 Number of n X n binary arrays with all ones connected only in a 3X3 plus 2,1 2,2 2,3 1,2 3,2.

1, 1, 2, 5, 12, 51, 317, 2654, 30351, 489559, 11104536, 350752586, 15493779226, 954798521885, 82299096564021, 9909284745619443, 1667319814728326908, 391914922807260266420, 128722643370894309970881

Offset

1,3

Links

Table of n, a(n) for n=1..19.

Example

Maximal 8 X 8 example
.0.0.0.0.1.0.0.0
.0.1.0.1.1.1.0.0
.1.1.1.0.1.0.1.0
.0.1.0.1.0.1.1.1
.0.0.1.1.1.0.1.0
.0.1.0.1.0.1.0.0
.1.1.1.0.1.1.1.0
.0.1.0.0.0.1.0.0

Crossrefs

Sequence in context: A343813 A332791 A291484 * A067578 A109139 A038576

Adjacent sequences: A145994 A145995 A145996 * A145998 A145999 A146000

Keyword

nonn

Author

R. H. Hardin, Oct 26 2008

Status

approved