A146805 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 0110-1100-0111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 3, 15, 43, 67, 129, 405, 1595, 5363, 29827, 122435, 735349, 3608129, 24333239, 151164887, 1326517337

Offset

1,7

Links

Table of n, a(n) for n=1..21.

Example

Maximal 8 X 8 example
.0.1.0.0.0.1.1.0
.1.1.1.0.0.0.1.1
.1.0.1.0.1.1.1.0
.0.0.1.0.0.0.0.0
.0.0.0.0.0.1.0.0
.0.1.1.1.0.1.0.1
.1.1.0.0.0.1.1.1
.0.1.1.0.0.0.1.0

Crossrefs

Sequence in context: A093627 A192060 A316642 * A147057 A330322 A101165

Adjacent sequences: A146802 A146803 A146804 * A146806 A146807 A146808

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved