A146637 - OEIS

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A146637

Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1010-1111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 7, 21, 49, 223, 1043, 7899, 74561, 730567, 8688119, 134449641, 2597702163, 64827359403, 1993658503781, 73350618685271, 3327101809889351

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,6

LINKS

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

EXAMPLE

Maximal 8 X 8 example

.0.0.0.1.1.0.0.0

.0.0.0.0.1.1.0.0

.0.0.0.1.1.0.1.0

.1.0.1.0.1.0.1.1

.1.1.1.1.0.1.1.0

.0.1.0.0.1.0.1.1

.0.0.1.1.1.1.0.0

.0.0.0.1.0.1.0.0

CROSSREFS

Sequence in context: A011927 A163723 A146669 * A146701 A146613 A083012

Adjacent sequences: A146634 A146635 A146636 * A146638 A146639 A146640

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved