A146171 Number of n X n binary arrays with all ones connected only in a 110-100-111 pattern in any orientation.

1, 1, 9, 33, 89, 853, 34557, 906369, 18920177, 1254520087, 193995577775, 29705523106027, 5297235657600881

Offset

1,3

Links

Table of n, a(n) for n=1..13.

Example

Maximal 8 X 8 example
.1.1.1.0.0.0.0.0
.1.0.0.0.0.0.1.1
.1.1.0.0.0.0.0.1
.0.0.0.0.0.1.1.1
.0.0.1.1.1.0.0.0
.1.1.0.0.1.0.1.1
.1.0.0.1.1.0.0.1
.1.1.1.0.0.1.1.1

Crossrefs

Sequence in context: A146256 A005920 A020324 * A146188 A020228 A005939

Adjacent sequences: A146168 A146169 A146170 * A146172 A146173 A146174

Keyword

nonn

Author

R. H. Hardin, Oct 27 2008

Status

approved