A146912 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 0100-1110-0111-0010 pattern in any orientation.

1, 1, 1, 3, 5, 9, 19, 57, 217, 857, 3619, 18707, 117969, 876253, 7474981, 73822321, 851878121, 11545709859, 183325972139, 3408618427993, 73952504878933, 1873630369319687, 55462085673863451, 1920965075733048401

Offset

1,4

Links

Table of n, a(n) for n=1..24.

Example

Maximal 8 X 8 example
.0.1.0.0.0.1.0.0
.1.1.1.0.1.1.1.0
.0.1.1.1.0.1.1.1
.0.0.1.0.0.0.1.0
.0.1.0.0.0.1.0.0
.1.1.1.0.1.1.1.0
.0.1.1.1.0.1.1.1
.0.0.1.0.0.0.1.0

Crossrefs

Sequence in context: A107028 A147470 A147010 * A146940 A146251 A281732

Adjacent sequences: A146909 A146910 A146911 * A146913 A146914 A146915

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved