A146152 Number of n X n binary arrays with all ones connected only either as two by three or three by two blocks.

1, 1, 5, 13, 47, 375, 3972, 47068, 892007, 26215027, 1025956370, 55524872121, 4474246357794, 516153334755405, 83220252331733856, 19182699863712254411

Offset

1,3

Links

Table of n, a(n) for n=1..16.

Example

Maximal 8 X 8 example
.1.1.1.0.0.1.1.1
.1.1.1.0.0.1.1.1
.0.0.0.0.0.0.0.0
.1.1.1.0.0.1.1.1
.1.1.1.0.0.1.1.1
.0.0.0.0.0.0.0.0
.0.1.1.1.0.1.1.1
.0.1.1.1.0.1.1.1

Crossrefs

Sequence in context: A162563 A250133 A025545 * A082132 A220900 A138277

Adjacent sequences: A146149 A146150 A146151 * A146153 A146154 A146155

Keyword

nonn

Author

R. H. Hardin, Oct 27 2008

Status

approved