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A146424 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1010-1111 pattern in any orientation. 0
1, 1, 1, 1, 3, 13, 35, 165, 727, 4597, 49361, 536263, 7236179, 123419355, 2560850455, 72571417743, 2591027414559, 113550328451315, 6265506511430339, 433231100847867929 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..20.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.1.1.0.0.0

.0.0.0.0.1.0.0.0

.0.0.0.1.1.0.0.0

.1.0.1.0.1.0.1.1

.1.1.1.1.0.0.0.1

.0.0.0.0.0.0.1.1

.0.0.0.1.0.1.0.1

.0.0.0.1.1.1.1.0

CROSSREFS

Sequence in context: A322187 A146741 A146725 * A146049 A061483 A340410

Adjacent sequences:  A146421 A146422 A146423 * A146425 A146426 A146427

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved

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Last modified December 4 02:40 EST 2021. Contains 349469 sequences. (Running on oeis4.)