A146778 - OEIS

A146778

Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 0010-1010-1111 pattern in any orientation.

1, 1, 1, 1, 1, 5, 17, 43, 145, 633, 4131, 31831, 267243, 2665825, 33726547, 521722083, 9834245987, 228276099483, 6476476460303, 221310304612835, 9127636122908961

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OFFSET

1,6

LINKS

Table of n, a(n) for n=1..21.

EXAMPLE

Maximal 8 X 8 example

.0.0.1.1.1.1.0.0

.0.0.1.0.1.0.0.0

.1.1.0.0.1.0.0.1

.1.0.0.0.0.1.1.1

.1.1.1.0.0.0.0.1

.1.0.0.1.0.0.1.1

.0.0.0.1.0.1.0.0

.0.0.1.1.1.1.0.0

CROSSREFS

Sequence in context: A168617 A046916 A089527 * A146858 A146183 A163424

Adjacent sequences: A146775 A146776 A146777 * A146779 A146780 A146781

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved