A147151 - OEIS

A147151

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1100-0111-0010 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 5, 13, 25, 61, 195, 561, 1503, 6349, 34075, 171101, 895779, 5615365, 39425317, 281937999

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OFFSET

1,9

LINKS

Table of n, a(n) for n=1..22.

EXAMPLE

Maximal 9 X 9 example

.0.0.0.0.0.0.1.0.0

.0.0.0.0.0.1.1.0.0

.0.0.0.1.1.1.0.1.1

.0.0.1.0.1.0.1.1.0

.0.0.1.1.0.1.1.0.0

.0.1.1.0.1.0.1.0.0

.1.1.0.1.1.1.0.0.0

.0.0.1.1.0.0.0.0.0

.0.0.1.0.0.0.0.0.0

CROSSREFS

Sequence in context: A146283 A026373 A066885 * A057288 A107466 A098480

Adjacent sequences: A147148 A147149 A147150 * A147152 A147153 A147154

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved