A147431 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1010-1111-0101 pattern in any orientation.

1, 1, 1, 1, 1, 3, 9, 19, 43, 151, 665, 3477, 19383, 122069, 922803, 8541115, 92856889, 1171563865, 17291558591, 299747161375, 6126738372415, 147219368035745, 4156365837186519

Offset

1,6

Links

Table of n, a(n) for n=1..23.

Example

Maximal 8 X 8 example
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.0.0.0.0.1.0.1.0
.0.0.0.0.1.1.1.1
.0.0.1.1.0.1.0.1
.0.0.0.1.1.0.0.0
.0.0.1.1.0.0.0.0
.0.0.0.1.1.0.0.0

Crossrefs

Sequence in context: A075188 A051894 A146393 * A329145 A348377 A147334

Adjacent sequences: A147428 A147429 A147430 * A147432 A147433 A147434

Keyword

nonn

Author

R. H. Hardin

Status

approved