A146811 - OEIS

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A146811

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1010-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 3, 7, 15, 31, 65, 179, 483, 1549, 5893, 23203, 108809, 513209, 2742185, 15938025, 102500855

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

OFFSET

1,8

LINKS

Table of n, a(n) for n=1..22.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.1.1.1.1.0

.0.0.0.1.0.1.0.1

.0.0.0.1.0.0.1.1

.1.1.1.0.0.0.0.1

.1.0.0.0.0.1.1.1

.1.1.0.0.1.0.0.0

.1.0.1.0.1.0.0.0

.0.1.1.1.1.0.0.0

CROSSREFS

Sequence in context: A129984 A365530 A351707 * A147235 A024876 A146598

Adjacent sequences: A146808 A146809 A146810 * A146812 A146813 A146814

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved