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A146040 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 2X4 tee 1,1 1,2 1,3 2,3 1,4 in any orientation. 0
1, 1, 1, 1, 1, 1, 1, 1, 29, 29, 249, 249, 4021, 4021, 99935, 99935, 4398251, 4398251, 362789159, 362789159, 47338031953, 47338031953, 10727733486159, 10727733486159 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,9

LINKS

Table of n, a(n) for n=1..24.

EXAMPLE

Maximal 9 X 9 example

.1.0.0.1.0.1.0.0.1

.1.1.0.1.0.1.0.1.1

.1.0.1.1.0.1.1.0.1

.1.0.0.1.0.1.0.0.1

.0.0.0.0.0.0.0.0.0

.1.0.0.1.0.1.0.0.1

.1.0.1.1.0.1.1.0.1

.1.1.0.1.0.1.0.1.1

.1.0.0.1.0.1.0.0.1

CROSSREFS

Sequence in context: A146226 A146423 A146129 * A146017 A210267 A210309

Adjacent sequences:  A146037 A146038 A146039 * A146041 A146042 A146043

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 26 2008

STATUS

approved

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Last modified September 25 09:48 EDT 2020. Contains 337336 sequences. (Running on oeis4.)