A146249 Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 110-111-011 pattern in any orientation.

1, 1, 1, 1, 1, 1, 15, 25, 133, 219, 1457, 2933, 35543, 83075, 3126293, 8900677, 367544923, 1223346993, 70409245499, 274415748801, 28451137210333, 130416755525325, 25340889265975927, 137413067766905999

Offset

1,7

Links

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

Example

Maximal 8 X 8 example
.1.1.0.0.0.0.1.1
.1.1.1.0.0.1.1.1
.0.1.1.0.0.1.1.0
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.0.1.1.0.0.1.1.0
.1.1.1.0.0.1.1.1
.1.1.0.0.0.0.1.1

Crossrefs

Sequence in context: A336689 A347375 A062238 * A248834 A249109 A342221

Adjacent sequences: A146246 A146247 A146248 * A146250 A146251 A146252

Keyword

nonn

Author

R. H. Hardin

Status

approved