A146998 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 00100-00100-11111 pattern in any orientation.

1, 1, 1, 1, 1, 3, 8, 23, 61, 183, 609, 3021, 17551, 122559, 936997, 8112490, 77983308, 921842339, 13073413646, 221502161483, 4341535999765, 98829117614873, 2578684019463460, 79032276911025441

Offset

1,6

Links

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

Example

Maximal 8 X 8 example
.0.1.1.1.1.1.0.0
.1.0.0.1.0.0.0.0
.1.0.0.1.0.0.0.1
.1.1.1.0.0.0.0.1
.1.0.0.0.0.1.1.1
.1.0.0.0.1.0.0.1
.0.0.0.0.1.0.0.1
.0.0.1.1.1.1.1.0

Crossrefs

Sequence in context: A071618 A318861 A318819 * A261329 A248870 A103819

Adjacent sequences: A146995 A146996 A146997 * A146999 A147000 A147001

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved