A146620 - OEIS

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A146620

Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1001-1111 pattern in any orientation.

1, 1, 1, 1, 1, 5, 1, 13, 13, 77, 73, 597, 385, 9569, 4155, 164139, 53517, 3530729, 1280671, 136089779, 42489917, 6885316541, 1853052759, 545054905807, 122748998951, 61234243905707

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,6

LINKS

Table of n, a(n) for n=1..26.

EXAMPLE

Maximal 8 X 8 example

.0.0.1.1.1.1.0.0

.0.0.1.0.0.1.0.0

.1.1.0.0.0.0.1.1

.1.0.0.0.0.0.0.1

.1.1.0.0.0.0.1.1

.0.0.1.0.0.1.0.0

.0.0.1.1.1.1.0.0

CROSSREFS

Sequence in context: A147004 A319664 A205961 * A300291 A366159 A174504

Adjacent sequences: A146617 A146618 A146619 * A146621 A146622 A146623

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved