A145926 Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a tee 1,1 1,2 1,3 2,2 in any orientation.

1, 1, 5, 1, 30, 11, 1066, 349, 107926, 18649, 30463506, 4281564, 28469202195, 3104114083, 81975632480940, 6299974483160, 716618459027321854, 40647817503851905, 19639345520014570444862, 820703096331703481460

Offset

1,3

Links

Table of n, a(n) for n=1..20.

Example

Maximal 8 X 8 example
.1.0.0.0.0.0.0.1
.1.1.0.0.0.0.1.1
.1.0.0.0.0.0.0.1
.0.0.1.0.0.1.0.0
.0.1.1.0.0.1.1.0
.0.0.1.0.0.1.0.0
.0.1.0.0.0.0.1.0
.1.1.1.0.0.1.1.1

Crossrefs

Sequence in context: A144891 A135892 A049460 * A062140 A144355 A049353

Adjacent sequences: A145923 A145924 A145925 * A145927 A145928 A145929

Keyword

nonn

Author

R. H. Hardin, Oct 25 2008

Status

approved