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A146598

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1000-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 3, 7, 15, 31, 71, 203, 581, 2061, 8089, 33693, 163089, 819567, 4807311, 30022515, 215155907, 1673895429

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OFFSET

1,8

LINKS

Table of n, a(n) for n=1..23.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.1.1.1.1.0

.0.0.0.1.0.0.0.1

.1.1.1.0.0.0.0.1

.1.0.0.0.0.1.1.1

.1.0.0.0.1.0.0.0

.0.1.1.1.1.0.0.0

CROSSREFS

Sequence in context: A147235 A024876 A390661 * A147094 A326518 A147285

Adjacent sequences: A146595 A146596 A146597 * A146599 A146600 A146601

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

URL: https://oeis.org/A146598

⇱ A146598 - OEIS