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A146417 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1111-1000 pattern in any orientation. 0
1, 1, 1, 1, 1, 1, 1, 1, 4, 7, 14, 21, 51, 123, 453, 1219, 4641, 13599, 63683, 242234, 1440301, 6546459, 44699492, 239296946, 1977082524, 12922743339, 130202512826, 1020385455911, 12242346882334 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,9

LINKS

Table of n, a(n) for n=1..29.

EXAMPLE

Maximal 9 X 9 example

.0.0.0.0.0.1.0.0.0

.0.0.1.1.1.1.0.0.0

.0.1.0.0.0.1.0.0.0

.0.1.0.0.0.0.1.1.1

.0.1.0.0.0.0.0.1.0

.1.1.1.0.0.0.0.1.0

.0.0.0.1.0.0.0.1.0

.0.0.0.1.1.1.1.0.0

.0.0.0.1.0.0.0.0.0

CROSSREFS

Sequence in context: A201272 A147440 A146678 * A008370 A291877 A048241

Adjacent sequences:  A146414 A146415 A146416 * A146418 A146419 A146420

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved

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Last modified July 31 10:51 EDT 2021. Contains 346373 sequences. (Running on oeis4.)