A146904 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 0010-1110-0111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 3, 7, 13, 27, 81, 287, 1153, 4961, 23911, 134777, 885445, 6659249, 57412261, 568445509, 6410206283, 82425528579, 1216468689493, 20669872378163, 403437418129203, 9012600422728359, 230172718811608655, 6730737235950056465

Offset

1,7

Links

Table of n, a(n) for n=1..28.

Example

Maximal 8 X 8 example
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.1.0
.0.0.0.0.1.1.1.0
.0.0.0.0.0.1.1.1
.0.0.1.0.0.1.0.0
.0.0.1.1.1.0.0.0
.0.1.1.1.0.0.0.0
.0.0.0.1.0.0.0.0

Crossrefs

Sequence in context: A080241 A098479 A119445 * A146432 A258349 A089726

Adjacent sequences: A146901 A146902 A146903 * A146905 A146906 A146907

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved