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A147286 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-0111-0001-0001 pattern in any orientation. 0
1, 1, 1, 1, 1, 1, 1, 1, 5, 9, 25, 53, 175 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,9

LINKS

Table of n, a(n) for n=1..13.

EXAMPLE

Maximal 9 X 9 example

.0.0.0.0.0.1.1.1.0

.0.0.0.0.0.1.0.0.1

.0.0.0.0.1.1.0.0.1

.0.0.0.0.1.0.1.1.1

.0.0.1.1.0.1.1.0.0

.1.1.1.0.1.0.0.0.0

.1.0.0.1.1.0.0.0.0

.1.0.0.1.0.0.0.0.0

.0.1.1.1.0.0.0.0.0

CROSSREFS

Sequence in context: A147383 A276918 A127976 * A137199 A221567 A147512

Adjacent sequences:  A147283 A147284 A147285 * A147287 A147288 A147289

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified December 4 15:36 EST 2021. Contains 349526 sequences. (Running on oeis4.)