A146372 - OEIS

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A146372

Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 0100-1111-0010 pattern in any orientation.

1, 1, 1, 1, 1, 13, 27, 135, 531, 2573, 17743, 176473, 1599401, 23234641, 323134671, 6982586189, 150620917453, 4817580729223, 154870862911911

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OFFSET

1,6

LINKS

Table of n, a(n) for n=1..19.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.0.0.1.0.0

.0.0.0.0.1.1.1.1

.0.1.0.0.0.0.1.0

.1.1.1.1.0.1.0.0

.0.0.1.0.1.1.1.1

.0.1.0.0.0.0.1.0

.1.1.1.1.0.0.0.0

.0.0.1.0.0.0.0.0

CROSSREFS

Sequence in context: A041332 A041334 A146380 * A018946 A042397 A041336

Adjacent sequences: A146369 A146370 A146371 * A146373 A146374 A146375

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved